Tag Archives: Sync

Google & Apple Order Telegram to Nuke Channel Over Taylor Swift Piracy

Post Syndicated from Andy original https://torrentfreak.com/google-apple-order-telegram-to-nuke-channel-over-taylor-swift-piracy-171123/

Financed by Russian Facebook (vKontakte) founder Pavel Durov, Telegram is a multi-platform messaging system that has grown from 100,000 daily users in 2013 to an impressive 100 million users in February 2016.

“Telegram is a messaging app with a focus on speed and security, it’s super-fast, simple and free. You can use Telegram on all your devices at the same time — your messages sync seamlessly across any number of your phones, tablets or computers,” the company’s marketing reads.

One of the attractive things about Telegram is that it allows users to communicate with each other using end-to-end encryption. In some cases, these systems are used for content piracy, of music and other smaller files in particular. This is compounded by the presence of user-programmed bots, which are able to search the web for illegal content and present it in a Telegram channel to which other users can subscribe.

While much of this sharing files under the radar when conducted privately, it periodically attracts attention from copyright holders when it takes place in public channels. That appears to have happened recently when popular channel “Any Suitable Pop” was completely disabled by Telegram, an apparent first following a copyright complaint.

According to channel creator Anton Vagin, the action by Telegram was probably due to the unauthorized recent sharing of the Taylor Swift album ‘Reputation’. However, it was the route of complaint that proves of most interest.

Rather than receiving a takedown notice directly from Big Machine Records, the label behind Swift’s releases, Telegram was forced into action after receiving threats from Apple and Google, the companies that distribute the Telegram app for iOS and Android respectively.

According to a message Vagin received from Telegram support, Apple and Google had received complaints about Swift’s album from Universal Music, the distributor of Big Machine Records. The suggestion was that if Telegram didn’t delete the infringing channel, distribution of the Telegram app via iTunes and Google Play would be at risk. Vagin received no warning notices from any of the companies involved.

Message from Telegram support

According to Russian news outlet VC.ru, which first reported the news, the channel was blocked in Telegram’s desktop applications, as well as in versions for Android, macOS and iOS. However, the channel still existed on the web and via Windows phone applications but all messages within had been deleted.

The fact that Google played a major role in the disappearing of the channel was subsequently confirmed by Telegram founder Pavel Durov, who commented that it was Google who “ultimately demanded the blocking of this channel.”

That Telegram finally caved into the demands of Google and/or Apple doesn’t really come as a surprise. In Telegram’s frequently asked questions section, the company specifically mentions the need to comply with copyright takedown demands in order to maintain distribution via the companies’ app marketplaces.

“Our mission is to provide a secure means of communication that works everywhere on the planet. To do this in the places where it is most needed (and to continue distributing Telegram through the App Store and Google Play), we have to process legitimate requests to take down illegal public content (sticker sets, bots, and channels) within the app,” the company notes.

Putting pressure on Telegram via Google and Apple over piracy isn’t a new development. In the past, representatives of the music industry threatened to complain to the companies over a channel operated by torrent site RuTracker, which was set up to share magnet links.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and more. We also have VPN discounts, offers and coupons

Event-Driven Computing with Amazon SNS and AWS Compute, Storage, Database, and Networking Services

Post Syndicated from Christie Gifrin original https://aws.amazon.com/blogs/compute/event-driven-computing-with-amazon-sns-compute-storage-database-and-networking-services/

Contributed by Otavio Ferreira, Manager, Software Development, AWS Messaging

Like other developers around the world, you may be tackling increasingly complex business problems. A key success factor, in that case, is the ability to break down a large project scope into smaller, more manageable components. A service-oriented architecture guides you toward designing systems as a collection of loosely coupled, independently scaled, and highly reusable services. Microservices take this even further. To improve performance and scalability, they promote fine-grained interfaces and lightweight protocols.

However, the communication among isolated microservices can be challenging. Services are often deployed onto independent servers and don’t share any compute or storage resources. Also, you should avoid hard dependencies among microservices, to preserve maintainability and reusability.

If you apply the pub/sub design pattern, you can effortlessly decouple and independently scale out your microservices and serverless architectures. A pub/sub messaging service, such as Amazon SNS, promotes event-driven computing that statically decouples event publishers from subscribers, while dynamically allowing for the exchange of messages between them. An event-driven architecture also introduces the responsiveness needed to deal with complex problems, which are often unpredictable and asynchronous.

What is event-driven computing?

Given the context of microservices, event-driven computing is a model in which subscriber services automatically perform work in response to events triggered by publisher services. This paradigm can be applied to automate workflows while decoupling the services that collectively and independently work to fulfil these workflows. Amazon SNS is an event-driven computing hub, in the AWS Cloud, that has native integration with several AWS publisher and subscriber services.

Which AWS services publish events to SNS natively?

Several AWS services have been integrated as SNS publishers and, therefore, can natively trigger event-driven computing for a variety of use cases. In this post, I specifically cover AWS compute, storage, database, and networking services, as depicted below.

Compute services

  • Auto Scaling: Helps you ensure that you have the correct number of Amazon EC2 instances available to handle the load for your application. You can configure Auto Scaling lifecycle hooks to trigger events, as Auto Scaling resizes your EC2 cluster.As an example, you may want to warm up the local cache store on newly launched EC2 instances, and also download log files from other EC2 instances that are about to be terminated. To make this happen, set an SNS topic as your Auto Scaling group’s notification target, then subscribe two Lambda functions to this SNS topic. The first function is responsible for handling scale-out events (to warm up cache upon provisioning), whereas the second is in charge of handling scale-in events (to download logs upon termination).

  • AWS Elastic Beanstalk: An easy-to-use service for deploying and scaling web applications and web services developed in a number of programming languages. You can configure event notifications for your Elastic Beanstalk environment so that notable events can be automatically published to an SNS topic, then pushed to topic subscribers.As an example, you may use this event-driven architecture to coordinate your continuous integration pipeline (such as Jenkins CI). That way, whenever an environment is created, Elastic Beanstalk publishes this event to an SNS topic, which triggers a subscribing Lambda function, which then kicks off a CI job against your newly created Elastic Beanstalk environment.

  • Elastic Load Balancing: Automatically distributes incoming application traffic across Amazon EC2 instances, containers, or other resources identified by IP addresses.You can configure CloudWatch alarms on Elastic Load Balancing metrics, to automate the handling of events derived from Classic Load Balancers. As an example, you may leverage this event-driven design to automate latency profiling in an Amazon ECS cluster behind a Classic Load Balancer. In this example, whenever your ECS cluster breaches your load balancer latency threshold, an event is posted by CloudWatch to an SNS topic, which then triggers a subscribing Lambda function. This function runs a task on your ECS cluster to trigger a latency profiling tool, hosted on the cluster itself. This can enhance your latency troubleshooting exercise by making it timely.

Storage services

  • Amazon S3: Object storage built to store and retrieve any amount of data.You can enable S3 event notifications, and automatically get them posted to SNS topics, to automate a variety of workflows. For instance, imagine that you have an S3 bucket to store incoming resumes from candidates, and a fleet of EC2 instances to encode these resumes from their original format (such as Word or text) into a portable format (such as PDF).In this example, whenever new files are uploaded to your input bucket, S3 publishes these events to an SNS topic, which in turn pushes these messages into subscribing SQS queues. Then, encoding workers running on EC2 instances poll these messages from the SQS queues; retrieve the original files from the input S3 bucket; encode them into PDF; and finally store them in an output S3 bucket.

  • Amazon EFS: Provides simple and scalable file storage, for use with Amazon EC2 instances, in the AWS Cloud.You can configure CloudWatch alarms on EFS metrics, to automate the management of your EFS systems. For example, consider a highly parallelized genomics analysis application that runs against an EFS system. By default, this file system is instantiated on the “General Purpose” performance mode. Although this performance mode allows for lower latency, it might eventually impose a scaling bottleneck. Therefore, you may leverage an event-driven design to handle it automatically.Basically, as soon as the EFS metric “Percent I/O Limit” breaches 95%, CloudWatch could post this event to an SNS topic, which in turn would push this message into a subscribing Lambda function. This function automatically creates a new file system, this time on the “Max I/O” performance mode, then switches the genomics analysis application to this new file system. As a result, your application starts experiencing higher I/O throughput rates.

  • Amazon Glacier: A secure, durable, and low-cost cloud storage service for data archiving and long-term backup.You can set a notification configuration on an Amazon Glacier vault so that when a job completes, a message is published to an SNS topic. Retrieving an archive from Amazon Glacier is a two-step asynchronous operation, in which you first initiate a job, and then download the output after the job completes. Therefore, SNS helps you eliminate polling your Amazon Glacier vault to check whether your job has been completed, or not. As usual, you may subscribe SQS queues, Lambda functions, and HTTP endpoints to your SNS topic, to be notified when your Amazon Glacier job is done.

  • AWS Snowball: A petabyte-scale data transport solution that uses secure appliances to transfer large amounts of data.You can leverage Snowball notifications to automate workflows related to importing data into and exporting data from AWS. More specifically, whenever your Snowball job status changes, Snowball can publish this event to an SNS topic, which in turn can broadcast the event to all its subscribers.As an example, imagine a Geographic Information System (GIS) that distributes high-resolution satellite images to users via Web browser. In this example, the GIS vendor could capture up to 80 TB of satellite images; create a Snowball job to import these files from an on-premises system to an S3 bucket; and provide an SNS topic ARN to be notified upon job status changes in Snowball. After Snowball changes the job status from “Importing” to “Completed”, Snowball publishes this event to the specified SNS topic, which delivers this message to a subscribing Lambda function, which finally creates a CloudFront web distribution for the target S3 bucket, to serve the images to end users.

Database services

  • Amazon RDS: Makes it easy to set up, operate, and scale a relational database in the cloud.RDS leverages SNS to broadcast notifications when RDS events occur. As usual, these notifications can be delivered via any protocol supported by SNS, including SQS queues, Lambda functions, and HTTP endpoints.As an example, imagine that you own a social network website that has experienced organic growth, and needs to scale its compute and database resources on demand. In this case, you could provide an SNS topic to listen to RDS DB instance events. When the “Low Storage” event is published to the topic, SNS pushes this event to a subscribing Lambda function, which in turn leverages the RDS API to increase the storage capacity allocated to your DB instance. The provisioning itself takes place within the specified DB maintenance window.

  • Amazon ElastiCache: A web service that makes it easy to deploy, operate, and scale an in-memory data store or cache in the cloud.ElastiCache can publish messages using Amazon SNS when significant events happen on your cache cluster. This feature can be used to refresh the list of servers on client machines connected to individual cache node endpoints of a cache cluster. For instance, an ecommerce website fetches product details from a cache cluster, with the goal of offloading a relational database and speeding up page load times. Ideally, you want to make sure that each web server always has an updated list of cache servers to which to connect.To automate this node discovery process, you can get your ElastiCache cluster to publish events to an SNS topic. Thus, when ElastiCache event “AddCacheNodeComplete” is published, your topic then pushes this event to all subscribing HTTP endpoints that serve your ecommerce website, so that these HTTP servers can update their list of cache nodes.

  • Amazon Redshift: A fully managed data warehouse that makes it simple to analyze data using standard SQL and BI (Business Intelligence) tools.Amazon Redshift uses SNS to broadcast relevant events so that data warehouse workflows can be automated. As an example, imagine a news website that sends clickstream data to a Kinesis Firehose stream, which then loads the data into Amazon Redshift, so that popular news and reading preferences might be surfaced on a BI tool. At some point though, this Amazon Redshift cluster might need to be resized, and the cluster enters a ready-only mode. Hence, this Amazon Redshift event is published to an SNS topic, which delivers this event to a subscribing Lambda function, which finally deletes the corresponding Kinesis Firehose delivery stream, so that clickstream data uploads can be put on hold.At a later point, after Amazon Redshift publishes the event that the maintenance window has been closed, SNS notifies a subscribing Lambda function accordingly, so that this function can re-create the Kinesis Firehose delivery stream, and resume clickstream data uploads to Amazon Redshift.

  • AWS DMS: Helps you migrate databases to AWS quickly and securely. The source database remains fully operational during the migration, minimizing downtime to applications that rely on the database.DMS also uses SNS to provide notifications when DMS events occur, which can automate database migration workflows. As an example, you might create data replication tasks to migrate an on-premises MS SQL database, composed of multiple tables, to MySQL. Thus, if replication tasks fail due to incompatible data encoding in the source tables, these events can be published to an SNS topic, which can push these messages into a subscribing SQS queue. Then, encoders running on EC2 can poll these messages from the SQS queue, encode the source tables into a compatible character set, and restart the corresponding replication tasks in DMS. This is an event-driven approach to a self-healing database migration process.

Networking services

  • Amazon Route 53: A highly available and scalable cloud-based DNS (Domain Name System). Route 53 health checks monitor the health and performance of your web applications, web servers, and other resources.You can set CloudWatch alarms and get automated Amazon SNS notifications when the status of your Route 53 health check changes. As an example, imagine an online payment gateway that reports the health of its platform to merchants worldwide, via a status page. This page is hosted on EC2 and fetches platform health data from DynamoDB. In this case, you could configure a CloudWatch alarm for your Route 53 health check, so that when the alarm threshold is breached, and the payment gateway is no longer considered healthy, then CloudWatch publishes this event to an SNS topic, which pushes this message to a subscribing Lambda function, which finally updates the DynamoDB table that populates the status page. This event-driven approach avoids any kind of manual update to the status page visited by merchants.

  • AWS Direct Connect (AWS DX): Makes it easy to establish a dedicated network connection from your premises to AWS, which can reduce your network costs, increase bandwidth throughput, and provide a more consistent network experience than Internet-based connections.You can monitor physical DX connections using CloudWatch alarms, and send SNS messages when alarms change their status. As an example, when a DX connection state shifts to 0 (zero), indicating that the connection is down, this event can be published to an SNS topic, which can fan out this message to impacted servers through HTTP endpoints, so that they might reroute their traffic through a different connection instead. This is an event-driven approach to connectivity resilience.

More event-driven computing on AWS

In addition to SNS, event-driven computing is also addressed by Amazon CloudWatch Events, which delivers a near real-time stream of system events that describe changes in AWS resources. With CloudWatch Events, you can route each event type to one or more targets, including:

Many AWS services publish events to CloudWatch. As an example, you can get CloudWatch Events to capture events on your ETL (Extract, Transform, Load) jobs running on AWS Glue and push failed ones to an SQS queue, so that you can retry them later.

Conclusion

Amazon SNS is a pub/sub messaging service that can be used as an event-driven computing hub to AWS customers worldwide. By capturing events natively triggered by AWS services, such as EC2, S3 and RDS, you can automate and optimize all kinds of workflows, namely scaling, testing, encoding, profiling, broadcasting, discovery, failover, and much more. Business use cases presented in this post ranged from recruiting websites, to scientific research, geographic systems, social networks, retail websites, and news portals.

Start now by visiting Amazon SNS in the AWS Management Console, or by trying the AWS 10-Minute Tutorial, Send Fan-out Event Notifications with Amazon SNS and Amazon SQS.

 

B2 Cloud Storage Roundup

Post Syndicated from Andy Klein original https://www.backblaze.com/blog/b2-cloud-storage-roundup/

B2 Integrations
Over the past several months, B2 Cloud Storage has continued to grow like we planted magic beans. During that time we have added a B2 Java SDK, and certified integrations with GoodSync, Arq, Panic, UpdraftPlus, Morro Data, QNAP, Archiware, Restic, and more. In addition, B2 customers like Panna Cooking, Sermon Audio, and Fellowship Church are happy they chose B2 as their cloud storage provider. If any of that sounds interesting, read on.

The B2 Java SDK

While the Backblaze B2 API is well documented and straight-forward to implement, we were asked by a few of our Integration Partners if we had an SDK they could use. So we developed one as an open-course project on GitHub, where we hope interested parties will not only use our Java SDK, but make it better for everyone else.

There are different reasons one might use the Java SDK, but a couple of areas where the SDK can simplify the coding process are:

Expiring Authorization — B2 requires an application key for a given account be reissued once a day when using the API. If the application key expires while you are in the middle of transferring files or some other B2 activity (bucket list, etc.), the SDK can be used to detect and then update the application key on the fly. Your B2 related activities will continue without incident and without having to capture and code your own exception case.

Error Handling — There are different types of error codes B2 will return, from expired application keys to detecting malformed requests to command time-outs. The SDK can dramatically simplify the coding needed to capture and account for the various things that can happen.

While Backblaze has created the Java SDK, developers in the GitHub community have also created other SDKs for B2, for example, for PHP (https://github.com/cwhite92/b2-sdk-php,) and Go (https://github.com/kurin/blazer.) Let us know in the comments about other SDKs you’d like to see or perhaps start your own GitHub project. We will publish any updates in our next B2 roundup.

What You Can Do with Affordable and Available Cloud Storage

You’re probably aware that B2 is up to 75% less expensive than other similar cloud storage services like Amazon S3 and Microsoft Azure. Businesses and organizations are finding that projects that previously weren’t economically feasible with other Cloud Storage services are now not only possible, but a reality with B2. Here are a few recent examples:

SermonAudio logo SermonAudio wanted their media files to be readily available, but didn’t want to build and manage their own internal storage farm. Until B2, cloud storage was just too expensive to use. Now they use B2 to store their audio and video files, and also as the primary source of downloads and streaming requests from their subscribers.
Fellowship Church logo Fellowship Church wanted to escape from the ever increasing amount of time they were spending saving their data to their LTO-based system. Using B2 saved countless hours of personnel time versus LTO, fit easily into their video processing workflow, and provided instant access at any time to their media library.
Panna logo Panna Cooking replaced their closet full of archive hard drives with a cost-efficient hybrid-storage solution combining 45Drives and Backblaze B2 Cloud Storage. Archived media files that used to take hours to locate are now readily available regardless of whether they reside in local storage or in the B2 Cloud.

B2 Integrations

Leading companies in backup, archive, and sync continue to add B2 Cloud Storage as a storage destination for their customers. These companies realize that by offering B2 as an option, they can dramatically lower the total cost of ownership for their customers — and that’s always a good thing.

If your favorite application is not integrated to B2, you can do something about it. One integration partner told us they received over 200 customer requests for a B2 integration. The partner got the message and the integration is currently in beta test.

Below are some of the partner integrations completed in the past few months. You can check the B2 Partner Integrations page for a complete list.

Archiware — Both P5 Archive and P5 Backup can now store data in the B2 Cloud making your offsite media files readily available while keeping your off-site storage costs predictable and affordable.

Arq — Combine Arq and B2 for amazingly affordable backup of external drives, network drives, NAS devices, Windows PCs, Windows Servers, and Macs to the cloud.

GoodSync — Automatically synchronize and back up all your photos, music, email, and other important files between all your desktops, laptops, servers, external drives, and sync, or back up to B2 Cloud Storage for off-site storage.

QNAP — QNAP Hybrid Backup Sync consolidates backup, restoration, and synchronization functions into a single QTS application to easily transfer your data to local, remote, and cloud storage.

Morro Data — Their CloudNAS solution stores files in the cloud, caches them locally as needed, and syncs files globally among other CloudNAS systems in an organization.

Restic – Restic is a fast, secure, multi-platform command line backup program. Files are uploaded to a B2 bucket as de-duplicated, encrypted chunks. Each backup is a snapshot of only the data that has changed, making restores of a specific date or time easy.

Transmit 5 by Panic — Transmit 5, the gold standard for macOS file transfer apps, now supports B2. Upload, download, and manage files on tons of servers with an easy, familiar, and powerful UI.

UpdraftPlus — WordPress developers and admins can now use the UpdraftPlus Premium WordPress plugin to affordably back up their data to the B2 Cloud.

Getting Started with B2 Cloud Storage

If you’re using B2 today, thank you. If you’d like to try B2, but don’t know where to start, here’s a guide to getting started with the B2 Web Interface — no programming or scripting is required. You get 10 gigabytes of free storage and 1 gigabyte a day in free downloads. Give it a try.

The post B2 Cloud Storage Roundup appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

Now Better Together! Register for and Attend this November 15 Tech Talk: “How to Integrate AWS Directory Service with Office 365”

Post Syndicated from Craig Liebendorfer original https://aws.amazon.com/blogs/security/now-better-together-register-for-and-attend-this-november-15-tech-talk-how-to-integrate-aws-directory-service-with-office-365/

AWS Online Tech Talks banner

As part of the AWS Online Tech Talks series, AWS will present How to Integrate AWS Directory Service with Office 365 on Wednesday, November 15. This tech talk will start at 9:00 A.M. Pacific Time and end at 9:40 A.M. Pacific Time.

If you want to support Active Directory–aware workloads in AWS and Office 365 simultaneously using a managed Active Directory in the cloud, you need a nonintuitive integration to synchronize identities between deployments. AWS has recently introduced the ability for you to authenticate your Office 365 permissions using AWS Directory Service for Microsoft Active Directory (AWS Managed Microsoft AD) by using a custom configuration of Active Directory Federation Services (AD FS). In this webinar, AWS Directory Service Product Manager Ron Cully shows how to configure your AWS Managed Microsoft AD environment to synchronize with Office 365. He will provide detailed configuration settings, architectural considerations, and deployment steps for a highly available, secure, and easy-to-manage solution in the AWS Cloud.

You also will learn how to:

  • Deploy AWS Managed Microsoft AD.
  • Deploy Microsoft Azure AD Connect and AD FS with AWS Managed Microsoft AD.
  • Authenticate user access to Office 365 by using AWS Managed Microsoft AD.

This tech talk is free. Register today.

– Craig

Introducing AWS Directory Service for Microsoft Active Directory (Standard Edition)

Post Syndicated from Peter Pereira original https://aws.amazon.com/blogs/security/introducing-aws-directory-service-for-microsoft-active-directory-standard-edition/

Today, AWS introduced AWS Directory Service for Microsoft Active Directory (Standard Edition), also known as AWS Microsoft AD (Standard Edition), which is managed Microsoft Active Directory (AD) that is performance optimized for small and midsize businesses. AWS Microsoft AD (Standard Edition) offers you a highly available and cost-effective primary directory in the AWS Cloud that you can use to manage users, groups, and computers. It enables you to join Amazon EC2 instances to your domain easily and supports many AWS and third-party applications and services. It also can support most of the common use cases of small and midsize businesses. When you use AWS Microsoft AD (Standard Edition) as your primary directory, you can manage access and provide single sign-on (SSO) to cloud applications such as Microsoft Office 365. If you have an existing Microsoft AD directory, you can also use AWS Microsoft AD (Standard Edition) as a resource forest that contains primarily computers and groups, allowing you to migrate your AD-aware applications to the AWS Cloud while using existing on-premises AD credentials.

In this blog post, I help you get started by answering three main questions about AWS Microsoft AD (Standard Edition):

  1. What do I get?
  2. How can I use it?
  3. What are the key features?

After answering these questions, I show how you can get started with creating and using your own AWS Microsoft AD (Standard Edition) directory.

1. What do I get?

When you create an AWS Microsoft AD (Standard Edition) directory, AWS deploys two Microsoft AD domain controllers powered by Microsoft Windows Server 2012 R2 in your Amazon Virtual Private Cloud (VPC). To help deliver high availability, the domain controllers run in different Availability Zones in the AWS Region of your choice.

As a managed service, AWS Microsoft AD (Standard Edition) configures directory replication, automates daily snapshots, and handles all patching and software updates. In addition, AWS Microsoft AD (Standard Edition) monitors and automatically recovers domain controllers in the event of a failure.

AWS Microsoft AD (Standard Edition) has been optimized as a primary directory for small and midsize businesses with the capacity to support approximately 5,000 employees. With 1 GB of directory object storage, AWS Microsoft AD (Standard Edition) has the capacity to store 30,000 or more total directory objects (users, groups, and computers). AWS Microsoft AD (Standard Edition) also gives you the option to add domain controllers to meet the specific performance demands of your applications. You also can use AWS Microsoft AD (Standard Edition) as a resource forest with a trust relationship to your on-premises directory.

2. How can I use it?

With AWS Microsoft AD (Standard Edition), you can share a single directory for multiple use cases. For example, you can share a directory to authenticate and authorize access for .NET applications, Amazon RDS for SQL Server with Windows Authentication enabled, and Amazon Chime for messaging and video conferencing.

The following diagram shows some of the use cases for your AWS Microsoft AD (Standard Edition) directory, including the ability to grant your users access to external cloud applications and allow your on-premises AD users to manage and have access to resources in the AWS Cloud. Click the diagram to see a larger version.

Diagram showing some ways you can use AWS Microsoft AD (Standard Edition)--click the diagram to see a larger version

Use case 1: Sign in to AWS applications and services with AD credentials

You can enable multiple AWS applications and services such as the AWS Management Console, Amazon WorkSpaces, and Amazon RDS for SQL Server to use your AWS Microsoft AD (Standard Edition) directory. When you enable an AWS application or service in your directory, your users can access the application or service with their AD credentials.

For example, you can enable your users to sign in to the AWS Management Console with their AD credentials. To do this, you enable the AWS Management Console as an application in your directory, and then assign your AD users and groups to IAM roles. When your users sign in to the AWS Management Console, they assume an IAM role to manage AWS resources. This makes it easy for you to grant your users access to the AWS Management Console without needing to configure and manage a separate SAML infrastructure.

Use case 2: Manage Amazon EC2 instances

Using familiar AD administration tools, you can apply AD Group Policy objects (GPOs) to centrally manage your Amazon EC2 for Windows or Linux instances by joining your instances to your AWS Microsoft AD (Standard Edition) domain.

In addition, your users can sign in to your instances with their AD credentials. This eliminates the need to use individual instance credentials or distribute private key (PEM) files. This makes it easier for you to instantly grant or revoke access to users by using AD user administration tools you already use.

Use case 3: Provide directory services to your AD-aware workloads

AWS Microsoft AD (Standard Edition) is an actual Microsoft AD that enables you to run traditional AD-aware workloads such as Remote Desktop Licensing Manager, Microsoft SharePoint, and Microsoft SQL Server Always On in the AWS Cloud. AWS Microsoft AD (Standard Edition) also helps you to simplify and improve the security of AD-integrated .NET applications by using group Managed Service Accounts (gMSAs) and Kerberos constrained delegation (KCD).

Use case 4: SSO to Office 365 and other cloud applications

You can use AWS Microsoft AD (Standard Edition) to provide SSO for cloud applications. You can use Azure AD Connect to synchronize your users into Azure AD, and then use Active Directory Federation Services (AD FS) so that your users can access Microsoft Office 365 and other SAML 2.0 cloud applications by using their AD credentials.

Use case 5: Extend your on-premises AD to the AWS Cloud

If you already have an AD infrastructure and want to use it when migrating AD-aware workloads to the AWS Cloud, AWS Microsoft AD (Standard Edition) can help. You can use AD trusts to connect AWS Microsoft AD (Standard Edition) to your existing AD. This means your users can access AD-aware and AWS applications with their on-premises AD credentials, without needing you to synchronize users, groups, or passwords.

For example, your users can sign in to the AWS Management Console and Amazon WorkSpaces by using their existing AD user names and passwords. Also, when you use AD-aware applications such as SharePoint with AWS Microsoft AD (Standard Edition), your logged-in Windows users can access these applications without needing to enter credentials again.

3. What are the key features?

AWS Microsoft AD (Standard Edition) includes the features detailed in this section.

Extend your AD schema

With AWS Microsoft AD, you can run customized AD-integrated applications that require changes to your directory schema, which defines the structures of your directory. The schema is composed of object classes such as user objects, which contain attributes such as user names. AWS Microsoft AD lets you extend the schema by adding new AD attributes or object classes that are not present in the core AD attributes and classes.

For example, if you have a human resources application that uses employee badge color to assign specific benefits, you can extend the schema to include a badge color attribute in the user object class of your directory. To learn more, see How to Move More Custom Applications to the AWS Cloud with AWS Directory Service.

Create user-specific password policies

With user-specific password policies, you can apply specific restrictions and account lockout policies to different types of users in your AWS Microsoft AD (Standard Edition) domain. For example, you can enforce strong passwords and frequent password change policies for administrators, and use less-restrictive policies with moderate account lockout policies for general users.

Add domain controllers

You can increase the performance and redundancy of your directory by adding domain controllers. This can help improve application performance by enabling directory clients to load-balance their requests across a larger number of domain controllers.

Encrypt directory traffic

You can use AWS Microsoft AD (Standard Edition) to encrypt Lightweight Directory Access Protocol (LDAP) communication between your applications and your directory. By enabling LDAP over Secure Sockets Layer (SSL)/Transport Layer Security (TLS), also called LDAPS, you encrypt your LDAP communications end to end. This helps you to protect sensitive information you keep in your directory when it is accessed over untrusted networks.

Improve the security of signing in to AWS services by using multi-factor authentication (MFA)

You can improve the security of signing in to AWS services, such as Amazon WorkSpaces and Amazon QuickSight, by enabling MFA in your AWS Microsoft AD (Standard Edition) directory. With MFA, your users must enter a one-time passcode (OTP) in addition to their AD user names and passwords to access AWS applications and services you enable in AWS Microsoft AD (Standard Edition).

Get started

To get started, use the Directory Service console to create your first directory with just a few clicks. If you have not used Directory Service before, you may be eligible for a 30-day limited free trial.

Summary

In this blog post, I explained what AWS Microsoft AD (Standard Edition) is and how you can use it. With a single directory, you can address many use cases for your business, making it easier to migrate and run your AD-aware workloads in the AWS Cloud, provide access to AWS applications and services, and connect to other cloud applications. To learn more about AWS Microsoft AD, see the Directory Service home page.

If you have comments about this post, submit them in the “Comments” section below. If you have questions about this blog post, start a new thread on the Directory Service forum.

– Peter

Automating Security Group Updates with AWS Lambda

Post Syndicated from Ian Scofield original https://aws.amazon.com/blogs/compute/automating-security-group-updates-with-aws-lambda/

Customers often use public endpoints to perform cross-region replication or other application layer communication to remote regions. But a common problem is how do you protect these endpoints? It can be tempting to open up the security groups to the world due to the complexity of keeping security groups in sync across regions with a dynamically changing infrastructure.

Consider a situation where you are running large clusters of instances in different regions that all require internode connectivity. One approach would be to use a VPN tunnel between regions to provide a secure tunnel over which to send your traffic. A good example of this is the Transit VPC Solution, which is a published AWS solution to help customers quickly get up and running. However, this adds additional cost and complexity to your solution due to the newly required additional infrastructure.

Another approach, which I’ll explore in this post, is to restrict access to the nodes by whitelisting the public IP addresses of your hosts in the opposite region. Today, I’ll outline a solution that allows for cross-region security group updates, can handle remote region failures, and supports external actions such as manually terminating instances or adding instances to an existing Auto Scaling group.

Solution overview

The overview of this solution is diagrammed below. Although this post covers limiting access to your instances, you should still implement encryption to protect your data in transit.

If your entire infrastructure is running in a single region, you can reference a security group as the source, allowing your IP addresses to change without any updates required. However, if you’re going across the public internet between regions to perform things like application-level traffic or cross-region replication, this is no longer an option. Security groups are regional. When you go across regions it can be tempting to drop security to enable this communication.

Although using an Elastic IP address can provide you with a static IP address that you can define as a source for your security groups, this may not always be feasible, especially when automatic scaling is desired.

In this example scenario, you have a distributed database that requires full internode communication for replication. If you place a cluster in us-east-1 and us-west-2, you must provide a secure method of communication between the two. Because the database uses cloud best practices, you can add or remove nodes as the load varies.

To start the process of updating your security groups, you must know when an instance has come online to trigger your workflow. Auto Scaling groups have the concept of lifecycle hooks that enable you to perform custom actions as the group launches or terminates instances.

When Auto Scaling begins to launch or terminate an instance, it puts the instance into a wait state (Pending:Wait or Terminating:Wait). The instance remains in this state while you perform your various actions until either you tell Auto Scaling to Continue, Abandon, or the timeout period ends. A lifecycle hook can trigger a CloudWatch event, publish to an Amazon SNS topic, or send to an Amazon SQS queue. For this example, you use CloudWatch Events to trigger an AWS Lambda function that updates an Amazon DynamoDB table.

Component breakdown

Here’s a quick breakdown of the components involved in this solution:

• Lambda function
• CloudWatch event
• DynamoDB table

Lambda function

The Lambda function automatically updates your security groups, in the following way:

1. Determines whether a change was triggered by your Auto Scaling group lifecycle hook or manually invoked for a “true up” functionality, which I discuss later in this post.
2. Describes the instances in the Auto Scaling group and obtain public IP addresses for each instance.
3. Updates both local and remote DynamoDB tables.
4. Compares the list of public IP addresses for both local and remote clusters with what’s already in the local region security group. Update the security group.
5. Compares the list of public IP addresses for both local and remote clusters with what’s already in the remote region security group. Update the security group
6. Signals CONTINUE back to the lifecycle hook.

CloudWatch event

The CloudWatch event triggers when an instance passes through either the launching or terminating states. When the Lambda function gets invoked, it receives an event that looks like the following:

{
	"account": "123456789012",
	"region": "us-east-1",
	"detail": {
		"LifecycleHookName": "hook-launching",
		"AutoScalingGroupName": "",
		"LifecycleActionToken": "33965228-086a-4aeb-8c26-f82ed3bef495",
		"LifecycleTransition": "autoscaling:EC2_INSTANCE_LAUNCHING",
		"EC2InstanceId": "i-017425ec54f22f994"
	},
	"detail-type": "EC2 Instance-launch Lifecycle Action",
	"source": "aws.autoscaling",
	"version": "0",
	"time": "2017-05-03T02:20:59Z",
	"id": "cb930cf8-ce8b-4b6c-8011-af17966eb7e2",
	"resources": [
		"arn:aws:autoscaling:us-east-1:123456789012:autoScalingGroup:d3fe9d96-34d0-4c62-b9bb-293a41ba3765:autoScalingGroupName/"
	]
}

DynamoDB table

You use DynamoDB to store lists of remote IP addresses in a local table that is updated by the opposite region as a failsafe source of truth. Although you can describe your Auto Scaling group for the local region, you must maintain a list of IP addresses for the remote region.

To minimize the number of describe calls and prevent an issue in the remote region from blocking your local scaling actions, we keep a list of the remote IP addresses in a local DynamoDB table. Each Lambda function in each region is responsible for updating the public IP addresses of its Auto Scaling group for both the local and remote tables.

As with all the infrastructure in this solution, there is a DynamoDB table in both regions that mirror each other. For example, the following screenshot shows a sample DynamoDB table. The Lambda function in us-east-1 would update the DynamoDB entry for us-east-1 in both tables in both regions.

By updating a DynamoDB table in both regions, it allows the local region to gracefully handle issues with the remote region, which would otherwise prevent your ability to scale locally. If the remote region becomes inaccessible, you have a copy of the latest configuration from the table that you can use to continue to sync with your security groups. When the remote region comes back online, it pushes its updated public IP addresses to the DynamoDB table. The security group is updated to reflect the current status by the remote Lambda function.

 

Walkthrough

Note: All of the following steps are performed in both regions. The Launch Stack buttons will default to the us-east-1 region.

Here’s a quick overview of the steps involved in this process:

1. An instance is launched or terminated, which triggers an Auto Scaling group lifecycle hook, triggering the Lambda function via CloudWatch Events.
2. The Lambda function retrieves the list of public IP addresses for all instances in the local region Auto Scaling group.
3. The Lambda function updates the local and remote region DynamoDB tables with the public IP addresses just received for the local Auto Scaling group.
4. The Lambda function updates the local region security group with the public IP addresses, removing and adding to ensure that it mirrors what is present for the local and remote Auto Scaling groups.
5. The Lambda function updates the remote region security group with the public IP addresses, removing and adding to ensure that it mirrors what is present for the local and remote Auto Scaling groups.

Prerequisites

To deploy this solution, you need to have Auto Scaling groups, launch configurations, and a base security group in both regions. To expedite this process, this CloudFormation template can be launched in both regions.

Step 1: Launch the AWS SAM template in the first region

To make the deployment process easy, I’ve created an AWS Serverless Application Model (AWS SAM) template, which is a new specification that makes it easier to manage and deploy serverless applications on AWS. This template creates the following resources:

• A Lambda function, to perform the various security group actions
• A DynamoDB table, to track the state of the local and remote Auto Scaling groups
• Auto Scaling group lifecycle hooks for instance launching and terminating
• A CloudWatch event, to track the EC2 Instance-Launch Lifecycle-Action and EC2 Instance-terminate Lifecycle-Action events
• A pointer from the CloudWatch event to the Lambda function, and the necessary permissions

Download the template from here or click to launch.

Upon launching the template, you’ll be presented with a list of parameters which includes the remote/local names for your Auto Scaling Groups, AWS region, Security Group IDs, DynamoDB table names, as well as where the code for the Lambda function is located. Because this is the first region you’re launching the stack in, fill out all the parameters except for the RemoteTable parameter as it hasn’t been created yet (you fill this in later).

Step 2: Test the local region

After the stack has finished launching, you can test the local region. Open the EC2 console and find the Auto Scaling group that was created when launching the prerequisite stack. Change the desired number of instances from 0 to 1.

For both regions, check your security group to verify that the public IP address of the instance created is now in the security group.

Local region:

Remote region:

Now, change the desired number of instances for your group back to 0 and verify that the rules are properly removed.

Local region:

Remote region:

Step 3: Launch in the remote region

When you deploy a Lambda function using CloudFormation, the Lambda zip file needs to reside in the same region you are launching the template. Once you choose your remote region, create an Amazon S3 bucket and upload the Lambda zip file there. Next, go to the remote region and launch the same SAM template as before, but make sure you update the CodeBucket and CodeKey parameters. Also, because this is the second launch, you now have all the values and can fill out all the parameters, specifically the RemoteTable value.

 

Step 4: Update the local region Lambda environment variable

When you originally launched the template in the local region, you didn’t have the name of the DynamoDB table for the remote region, because you hadn’t created it yet. Now that you have launched the remote template, you can perform a CloudFormation stack update on the initial SAM template. This populates the remote DynamoDB table name into the initial Lambda function’s environment variables.

In the CloudFormation console in the initial region, select the stack. Under Actions, choose Update Stack, and select the SAM template used for both regions. Under Parameters, populate the remote DynamoDB table name, as shown below. Choose Next and let the stack update complete. This updates your Lambda function and completes the setup process.

 

Step 5: Final testing

You now have everything fully configured and in place to trigger security group changes based on instances being added or removed to your Auto Scaling groups in both regions. Test this by changing the desired capacity of your group in both regions.

True up functionality
If an instance is manually added or removed from the Auto Scaling group, the lifecycle hooks don’t get triggered. To account for this, the Lambda function supports a “true up” functionality in which the function can be manually invoked. If you paste in the following JSON text for your test event, it kicks off the entire workflow. For added peace of mind, you can also have this function fire via a CloudWatch event with a CRON expression for nearly continuous checking.

{
	"detail": {
		"AutoScalingGroupName": "<your ASG name>"
	},
	"trueup":true
}

Extra credit

Now that all the resources are created in both regions, go back and break down the policy to incorporate resource-level permissions for specific security groups, Auto Scaling groups, and the DynamoDB tables.

Although this post is centered around using public IP addresses for your instances, you could instead use a VPN between regions. In this case, you would still be able to use this solution to scope down the security groups to the cluster instances. However, the code would need to be modified to support private IP addresses.

 

Conclusion

At this point, you now have a mechanism in place that captures when a new instance is added to or removed from your cluster and updates the security groups in both regions. This ensures that you are locking down your infrastructure securely by allowing access only to other cluster members.

Keep in mind that this architecture (lifecycle hooks, CloudWatch event, Lambda function, and DynamoDB table) requires that the infrastructure to be deployed in both regions, to have synchronization going both ways.

Because this Lambda function is modifying security group rules, it’s important to have an audit log of what has been modified and who is modifying them. The out-of-the-box function provides logs in CloudWatch for what IP addresses are being added and removed for which ports. As these are all API calls being made, they are logged in CloudTrail and can be traced back to the IAM role that you created for your lifecycle hooks. This can provide historical data that can be used for troubleshooting or auditing purposes.

Security is paramount at AWS. We want to ensure that customers are protecting access to their resources. This solution helps you keep your security groups in both regions automatically in sync with your Auto Scaling group resources. Let us know if you have any questions or other solutions you’ve come up with!

Blockchain? It’s All Greek To Me…

Post Syndicated from Bozho original https://techblog.bozho.net/blockchain-its-all-greek-to-me/

The blockchain hype is huge, the ICO craze (“Coindike”) is generating millions if not billions of “funding” for businesses that claim to revolutionize basically anything.

I’ve been following all of that for a while. I got my first (and only) Bitcoin several years ago, I know how the technology works, I’ve implemented the data structure part, I’ve tried (with varying success) to install an Ethereum wallet since almost as soon as Ethereum appeared, and I’ve read and subscribed to newsletters about dozens of projects and new cryptocurrencies, including storj.io, siacoin, namecoin, etc. I would say I’m at least above average in terms of knowledge on how the cryptocurrencies, blockchain, smart contracts, EVM, proof-of-wahtever operates. And I’ve voiced my concerns about the technology in general.

Now it’s rant time.

I’ve been reading whitepapers of various projects, I’ve been to various meetups and talks, I’ve been reading the professed future applications of the blockchain, and I have to admit – it’s all Greek to me. I have no clue what these people are talking about. And why would all of that make any sense. I still think I’m not clever enough to understand the upcoming revolution, but there’s also a cynical side of me that says “this is all a scam”.

Why “X on the blockchain” somehow makes it magical and superior to a good old centralized solution? No, spare me the cliches about “immutable ledger”, “lack of central authority” and the likes. These are the phrases that a person learns after reading literally one article about blockchain. Have you actually written anything apart from a complex-sounding whitepaper or a hello-world smart contract? Do you really know how the overlay network works, how the economic incentives behind that network work, how all the cryptography works? Maybe there are many, many people that indeed know that and they know it better than me and are thus able to imagine the business case behind “X on the blockchain”.

I can’t. I can’t see why it would be useful to abandon a centralized database that you can query in dozens of ways, test easily and scale trivially in favour of a clunky write-only, low-throughput, hard-to-debug privacy nightmare that is any public blockchain. And how do you imagine to gain a substantial userbase with an ecosystem where the Windows client for the 2nd most popular blockchain (Ethereum) has been so buggy, I (a software engineer) couldn’t get it work and sync the whole chain. And why would building a website ontop of that clunky, user-unfriendly database has any benefit over a centralized competitor?

Do we all believe that somehow the huge datacenters with guarnateed power backups, regular hardware and network checks, regular backups and overall – guaranteed redundancy – will somehow be beaten by a few thousand machines hosting a software that has the sole purpose of guaranteeing integrity? Bitcoin has 10 thousand nodes. Ethereum has 22 thousand nodes. And while these nodes are probably very well GPU-equipped, they aren’t supercomputers. Amazon’s AWS has a million servers. How’s that for comparison. And why would anyone take seriously 22 thousand non-servers. Or even 220 thousand, if we believe in some inevitable growth.

Don’t get me wrong, the technology is really cool. The way tamper-evident data structures (hash chains) were combined with a consensus algorithm, an overlay network and a financial incentive is really awesome. When you add a distributed execution environment, it gets even cooler. But is it suitable for literally everything? I fail to see how.

I’m sure I’m missing something. The fact that many of those whitepapers sound increasingly like Greek to me might hint that I’m just a dumb developer and those enlightened people are really onto something huge. I guess time will tell.

But I happen to be living in a country that saw a transition to capitalism in the years of my childhood. And there were a lot of scams and ponzi schemes that people believed in. Because they didn’t know how capitalism works, how the market works. I’m seeing some similarities – we have no idea how the digital realm really works, and so a lot of scams are bound to appear, until we as a society learn the basics.

Until then – enjoy your ICO, enjoy your tokens, enjoy your big-player competitor with practically the same business model, only on a worse database.

And I hope that after the smoke of hype and fraud clears, we’ll be able to enjoy the true benefits of the blockchain innovation.

The post Blockchain? It’s All Greek To Me… appeared first on Bozho's tech blog.

All Systems Go! 2017 Videos Online!

Post Syndicated from Lennart Poettering original http://0pointer.net/blog/all-systems-go-2017-videos-online.html

For those living under a rock, the videos from everybody’s favourite
Userspace Linux Conference All Systems Go!
2017
are now available online.

All videos

The videos for my own two talks are available here:

Synchronizing Images with
casync

(Slides)

Containers without a Container Manager, with
systemd

(Slides)

Of course, this is the stellar work of the CCC
VOC
folks, who are hard to beat when it comes to
videotaping of community conferences.

Enabling Two-Factor Authentication For Your Web Application

Post Syndicated from Bozho original https://techblog.bozho.net/enabling-two-factor-authentication-web-application/

It’s almost always a good idea to support two-factor authentication (2FA), especially for back-office systems. 2FA comes in many different forms, some of which include SMS, TOTP, or even hardware tokens.

Enabling them requires a similar flow:

  • The user goes to their profile page (skip this if you want to force 2fa upon registration)
  • Clicks “Enable two-factor authentication”
  • Enters some data to enable the particular 2FA method (phone number, TOTP verification code, etc.)
  • Next time they login, in addition to the username and password, the login form requests the 2nd factor (verification code) and sends that along with the credentials

I will focus on Google Authenticator, which uses a TOTP (Time-based one-time password) for generating a sequence of verification codes. The ideas is that the server and the client application share a secret key. Based on that key and on the current time, both come up with the same code. Of course, clocks are not perfectly synced, so there’s a window of a few codes that the server accepts as valid.

How to implement that with Java (on the server)? Using the GoogleAuth library. The flow is as follows:

  • The user goes to their profile page
  • Clicks “Enable two-factor authentication”
  • The server generates a secret key, stores it as part of the user profile and returns a URL to a QR code
  • The user scans the QR code with their Google Authenticator app thus creating a new profile in the app
  • The user enters the verification code shown the app in a field that has appeared together with the QR code and clicks “confirm”
  • The server marks the 2FA as enabled in the user profile
  • If the user doesn’t scan the code or doesn’t verify the process, the user profile will contain just a orphaned secret key, but won’t be marked as enabled
  • There should be an option to later disable the 2FA from their user profile page

The most important bit from theoretical point of view here is the sharing of the secret key. The crypto is symmetric, so both sides (the authenticator app and the server) have the same key. It is shared via a QR code that the user scans. If an attacker has control on the user’s machine at that point, the secret can be leaked and thus the 2FA – abused by the attacker as well. But that’s not in the threat model – in other words, if the attacker has access to the user’s machine, the damage is already done anyway.

Upon login, the flow is as follows:

  • The user enters username and password and clicks “Login”
  • Using an AJAX request the page asks the server whether this email has 2FA enabled
  • If 2FA is not enabled, just submit the username & password form
  • If 2FA is enabled, the login form is not submitted, but instead an additional field is shown to let the user input the verification code from the authenticator app
  • After the user enters the code and presses login, the form can be submitted. Either using the same login button, or a new “verify” button, or the verification input + button could be an entirely new screen (hiding the username/password inputs).
  • The server then checks again if the user has 2FA enabled and if yes, verifies the verification code. If it matches, login is successful. If not, login fails and the user is allowed to reenter the credentials and the verification code. Note here that you can have different responses depending on whether username/password are wrong or in case the code is wrong. You can also attempt to login prior to even showing the verification code input. That way is arguably better, because that way you don’t reveal to a potential attacker that the user uses 2FA.

While I’m speaking of username and password, that can apply to any other authentication method. After you get a success confirmation from an OAuth / OpenID Connect / SAML provider, or after you can a token from SecureLogin, you can request the second factor (code).

In code, the above processes look as follows (using Spring MVC; I’ve merged the controller and service layer for brevity. You can replace the @AuthenticatedPrincipal bit with your way of supplying the currently logged in user details to the controllers). Assuming the methods are in controller mapped to “/user/”:

@RequestMapping(value = "/init2fa", method = RequestMethod.POST)
@ResponseBody
public String initTwoFactorAuth(@AuthenticationPrincipal LoginAuthenticationToken token) {
    User user = getLoggedInUser(token);
    GoogleAuthenticatorKey googleAuthenticatorKey = googleAuthenticator.createCredentials();
    user.setTwoFactorAuthKey(googleAuthenticatorKey.getKey());
    dao.update(user);
    return GoogleAuthenticatorQRGenerator.getOtpAuthURL(GOOGLE_AUTH_ISSUER, email, googleAuthenticatorKey);
}

@RequestMapping(value = "/confirm2fa", method = RequestMethod.POST)
@ResponseBody
public boolean confirmTwoFactorAuth(@AuthenticationPrincipal LoginAuthenticationToken token, @RequestParam("code") int code) {
    User user = getLoggedInUser(token);
    boolean result = googleAuthenticator.authorize(user.getTwoFactorAuthKey(), code);
    user.setTwoFactorAuthEnabled(result);
    dao.update(user);
    return result;
}

@RequestMapping(value = "/disable2fa", method = RequestMethod.GET)
@ResponseBody
public void disableTwoFactorAuth(@AuthenticationPrincipal LoginAuthenticationToken token) {
    User user = getLoggedInUser(token);
    user.setTwoFactorAuthKey(null);
    user.setTwoFactorAuthEnabled(false);
    dao.update(user);
}

@RequestMapping(value = "/requires2fa", method = RequestMethod.POST)
@ResponseBody
public boolean login(@RequestParam("email") String email) {
    // TODO consider verifying the password here in order not to reveal that a given user uses 2FA
    return userService.getUserDetailsByEmail(email).isTwoFactorAuthEnabled();
}

On the client side it’s simple AJAX requests to the above methods (sidenote: I kind of feel the term AJAX is no longer trendy, but I don’t know how to call them. Async? Background? Javascript?).

$("#two-fa-init").click(function() {
    $.post("/user/init2fa", function(qrImage) {
	$("#two-fa-verification").show();
	$("#two-fa-qr").prepend($('<img>',{id:'qr',src:qrImage}));
	$("#two-fa-init").hide();
    });
});

$("#two-fa-confirm").click(function() {
    var verificationCode = $("#verificationCode").val().replace(/ /g,'')
    $.post("/user/confirm2fa?code=" + verificationCode, function() {
       $("#two-fa-verification").hide();
       $("#two-fa-qr").hide();
       $.notify("Successfully enabled two-factor authentication", "success");
       $("#two-fa-message").html("Successfully enabled");
    });
});

$("#two-fa-disable").click(function() {
    $.post("/user/disable2fa", function(qrImage) {
       window.location.reload();
    });
});

The login form code depends very much on the existing login form you are using, but the point is to call the /requires2fa with the email (and password) to check if 2FA is enabled and then show a verification code input.

Overall, the implementation if two-factor authentication is simple and I’d recommend it for most systems, where security is more important than simplicity of the user experience.

The post Enabling Two-Factor Authentication For Your Web Application appeared first on Bozho's tech blog.

Backing Up Linux to Backblaze B2 with Duplicity and Restic

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/backing-linux-backblaze-b2-duplicity-restic/

Linux users have a variety of options for handling data backup. The choices range from free and open-source programs to paid commercial tools, and include applications that are purely command-line based (CLI) and others that have a graphical interface (GUI), or both.

If you take a look at our Backblaze B2 Cloud Storage Integrations page, you will see a number of offerings that enable you to back up your Linux desktops and servers to Backblaze B2. These include CloudBerry, Duplicity, Duplicacy, 45 Drives, GoodSync, HashBackup, QNAP, Restic, and Rclone, plus other choices for NAS and hybrid uses.

In this post, we’ll discuss two popular command line and open-source programs: one older, Duplicity, and a new player, Restic.

Old School vs. New School

We’re highlighting Duplicity and Restic today because they exemplify two different philosophical approaches to data backup: “Old School” (Duplicity) vs “New School” (Restic).

Old School (Duplicity)

In the old school model, data is written sequentially to the storage medium. Once a section of data is recorded, new data is written starting where that section of data ends. It’s not possible to go back and change the data that’s already been written.

This old-school model has long been associated with the use of magnetic tape, a prime example of which is the LTO (Linear Tape-Open) standard. In this “write once” model, files are always appended to the end of the tape. If a file is modified and overwritten or removed from the volume, the associated tape blocks used are not freed up: they are simply marked as unavailable, and the used volume capacity is not recovered. Data is deleted and capacity recovered only if the whole tape is reformatted. As a Linux/Unix user, you undoubtedly are familiar with the TAR archive format, which is an acronym for Tape ARchive. TAR has been around since 1979 and was originally developed to write data to sequential I/O devices with no file system of their own.

It is from the use of tape that we get the full backup/incremental backup approach to backups. A backup sequence beings with a full backup of data. Each incremental backup contains what’s been changed since the last full backup until the next full backup is made and the process starts over, filling more and more tape or whatever medium is being used.

This is the model used by Duplicity: full and incremental backups. Duplicity backs up files by producing encrypted, digitally signed, versioned, TAR-format volumes and uploading them to a remote location, including Backblaze B2 Cloud Storage. Released under the terms of the GNU General Public License (GPL), Duplicity is free software.

With Duplicity, the first archive is a complete (full) backup, and subsequent (incremental) backups only add differences from the latest full or incremental backup. Chains consisting of a full backup and a series of incremental backups can be recovered to the point in time that any of the incremental steps were taken. If any of the incremental backups are missing, then reconstructing a complete and current backup is much more difficult and sometimes impossible.

Duplicity is available under many Unix-like operating systems (such as Linux, BSD, and Mac OS X) and ships with many popular Linux distributions including Ubuntu, Debian, and Fedora. It also can be used with Windows under Cygwin.

We recently published a KB article on How to configure Backblaze B2 with Duplicity on Linux that demonstrates how to set up Duplicity with B2 and back up and restore a directory from Linux.

New School (Restic)

With the arrival of non-sequential storage medium, such as disk drives, and new ideas such as deduplication, comes the new school approach, which is used by Restic. Data can be written and changed anywhere on the storage medium. This efficiency comes largely through the use of deduplication. Deduplication is a process that eliminates redundant copies of data and reduces storage overhead. Data deduplication techniques ensure that only one unique instance of data is retained on storage media, greatly increasing storage efficiency and flexibility.

Restic is a recently available multi-platform command line backup software program that is designed to be fast, efficient, and secure. Restic supports a variety of backends for storing backups, including a local server, SFTP server, HTTP Rest server, and a number of cloud storage providers, including Backblaze B2.

Files are uploaded to a B2 bucket as deduplicated, encrypted chunks. Each time a backup runs, only changed data is backed up. On each backup run, a snapshot is created enabling restores to a specific date or time.

Restic assumes that the storage location for repository is shared, so it always encrypts the backed up data. This is in addition to any encryption and security from the storage provider.

Restic is open source and free software and licensed under the BSD 2-Clause License and actively developed on GitHub.

There’s a lot more you can do with Restic, including adding tags, mounting a repository locally, and scripting. To learn more, you can review the documentation at https://restic.readthedocs.io.

Coincidentally with this blog post, we published a KB article, How to configure Backblaze B2 with Restic on Linux, in which we show how to set up Restic for use with B2 and how to back up and restore a home directory from Linux to B2.

Which is Right for You?

While Duplicity is a popular, widely-available, and useful program, many users of cloud storage solutions such as B2 are moving to new-school solutions like Restic that take better advantage of the non-sequential access capabilities and speed of modern storage media used by cloud storage providers.

Tell us how you’re backing up Linux

Please let us know in the comments what you’re using for Linux backups, and if you have experience using Duplicity, Restic, or other backup software with Backblaze B2.

The post Backing Up Linux to Backblaze B2 with Duplicity and Restic appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

Using AWS Step Functions State Machines to Handle Workflow-Driven AWS CodePipeline Actions

Post Syndicated from Marcilio Mendonca original https://aws.amazon.com/blogs/devops/using-aws-step-functions-state-machines-to-handle-workflow-driven-aws-codepipeline-actions/

AWS CodePipeline is a continuous integration and continuous delivery service for fast and reliable application and infrastructure updates. It offers powerful integration with other AWS services, such as AWS CodeBuildAWS CodeDeployAWS CodeCommit, AWS CloudFormation and with third-party tools such as Jenkins and GitHub. These services make it possible for AWS customers to successfully automate various tasks, including infrastructure provisioning, blue/green deployments, serverless deployments, AMI baking, database provisioning, and release management.

Developers have been able to use CodePipeline to build sophisticated automation pipelines that often require a single CodePipeline action to perform multiple tasks, fork into different execution paths, and deal with asynchronous behavior. For example, to deploy a Lambda function, a CodePipeline action might first inspect the changes pushed to the code repository. If only the Lambda code has changed, the action can simply update the Lambda code package, create a new version, and point the Lambda alias to the new version. If the changes also affect infrastructure resources managed by AWS CloudFormation, the pipeline action might have to create a stack or update an existing one through the use of a change set. In addition, if an update is required, the pipeline action might enforce a safety policy to infrastructure resources that prevents the deletion and replacement of resources. You can do this by creating a change set and having the pipeline action inspect its changes before updating the stack. Change sets that do not conform to the policy are deleted.

This use case is a good illustration of workflow-driven pipeline actions. These are actions that run multiple tasks, deal with async behavior and loops, need to maintain and propagate state, and fork into different execution paths. Implementing workflow-driven actions directly in CodePipeline can lead to complex pipelines that are hard for developers to understand and maintain. Ideally, a pipeline action should perform a single task and delegate the complexity of dealing with workflow-driven behavior associated with that task to a state machine engine. This would make it possible for developers to build simpler, more intuitive pipelines and allow them to use state machine execution logs to visualize and troubleshoot their pipeline actions.

In this blog post, we discuss how AWS Step Functions state machines can be used to handle workflow-driven actions. We show how a CodePipeline action can trigger a Step Functions state machine and how the pipeline and the state machine are kept decoupled through a Lambda function. The advantages of using state machines include:

  • Simplified logic (complex tasks are broken into multiple smaller tasks).
  • Ease of handling asynchronous behavior (through state machine wait states).
  • Built-in support for choices and processing different execution paths (through state machine choices).
  • Built-in visualization and logging of the state machine execution.

The source code for the sample pipeline, pipeline actions, and state machine used in this post is available at https://github.com/awslabs/aws-codepipeline-stepfunctions.

Overview

This figure shows the components in the CodePipeline-Step Functions integration that will be described in this post. The pipeline contains two stages: a Source stage represented by a CodeCommit Git repository and a Prod stage with a single Deploy action that represents the workflow-driven action.

This action invokes a Lambda function (1) called the State Machine Trigger Lambda, which, in turn, triggers a Step Function state machine to process the request (2). The Lambda function sends a continuation token back to the pipeline (3) to continue its execution later and terminates. Seconds later, the pipeline invokes the Lambda function again (4), passing the continuation token received. The Lambda function checks the execution state of the state machine (5,6) and communicates the status to the pipeline. The process is repeated until the state machine execution is complete. Then the Lambda function notifies the pipeline that the corresponding pipeline action is complete (7). If the state machine has failed, the Lambda function will then fail the pipeline action and stop its execution (7). While running, the state machine triggers various Lambda functions to perform different tasks. The state machine and the pipeline are fully decoupled. Their interaction is handled by the Lambda function.

The Deploy State Machine

The sample state machine used in this post is a simplified version of the use case, with emphasis on infrastructure deployment. The state machine will follow distinct execution paths and thus have different outcomes, depending on:

  • The current state of the AWS CloudFormation stack.
  • The nature of the code changes made to the AWS CloudFormation template and pushed into the pipeline.

If the stack does not exist, it will be created. If the stack exists, a change set will be created and its resources inspected by the state machine. The inspection consists of parsing the change set results and detecting whether any resources will be deleted or replaced. If no resources are being deleted or replaced, the change set is allowed to be executed and the state machine completes successfully. Otherwise, the change set is deleted and the state machine completes execution with a failure as the terminal state.

Let’s dive into each of these execution paths.

Path 1: Create a Stack and Succeed Deployment

The Deploy state machine is shown here. It is triggered by the Lambda function using the following input parameters stored in an S3 bucket.

Create New Stack Execution Path

{
    "environmentName": "prod",
    "stackName": "sample-lambda-app",
    "templatePath": "infra/Lambda-template.yaml",
    "revisionS3Bucket": "codepipeline-us-east-1-418586629775",
    "revisionS3Key": "StepFunctionsDrivenD/CodeCommit/sjcmExZ"
}

Note that some values used here are for the use case example only. Account-specific parameters like revisionS3Bucket and revisionS3Key will be different when you deploy this use case in your account.

These input parameters are used by various states in the state machine and passed to the corresponding Lambda functions to perform different tasks. For example, stackName is used to create a stack, check the status of stack creation, and create a change set. The environmentName represents the environment (for example, dev, test, prod) to which the code is being deployed. It is used to prefix the name of stacks and change sets.

With the exception of built-in states such as wait and choice, each state in the state machine invokes a specific Lambda function.  The results received from the Lambda invocations are appended to the state machine’s original input. When the state machine finishes its execution, several parameters will have been added to its original input.

The first stage in the state machine is “Check Stack Existence”. It checks whether a stack with the input name specified in the stackName input parameter already exists. The output of the state adds a Boolean value called doesStackExist to the original state machine input as follows:

{
  "doesStackExist": true,
  "environmentName": "prod",
  "stackName": "sample-lambda-app",
  "templatePath": "infra/lambda-template.yaml",
  "revisionS3Bucket": "codepipeline-us-east-1-418586629775",
  "revisionS3Key": "StepFunctionsDrivenD/CodeCommit/sjcmExZ",
}

The following stage, “Does Stack Exist?”, is represented by Step Functions built-in choice state. It checks the value of doesStackExist to determine whether a new stack needs to be created (doesStackExist=true) or a change set needs to be created and inspected (doesStackExist=false).

If the stack does not exist, the states illustrated in green in the preceding figure are executed. This execution path creates the stack, waits until the stack is created, checks the status of the stack’s creation, and marks the deployment successful after the stack has been created. Except for “Stack Created?” and “Wait Stack Creation,” each of these stages invokes a Lambda function. “Stack Created?” and “Wait Stack Creation” are implemented by using the built-in choice state (to decide which path to follow) and the wait state (to wait a few seconds before proceeding), respectively. Each stage adds the results of their Lambda function executions to the initial input of the state machine, allowing future stages to process them.

Path 2: Safely Update a Stack and Mark Deployment as Successful

Safely Update a Stack and Mark Deployment as Successful Execution Path

If the stack indicated by the stackName parameter already exists, a different path is executed. (See the green states in the figure.) This path will create a change set and use wait and choice states to wait until the change set is created. Afterwards, a stage in the execution path will inspect  the resources affected before the change set is executed.

The inspection procedure represented by the “Inspect Change Set Changes” stage consists of parsing the resources affected by the change set and checking whether any of the existing resources are being deleted or replaced. The following is an excerpt of the algorithm, where changeSetChanges.Changes is the object representing the change set changes:

...
var RESOURCES_BEING_DELETED_OR_REPLACED = "RESOURCES-BEING-DELETED-OR-REPLACED";
var CAN_SAFELY_UPDATE_EXISTING_STACK = "CAN-SAFELY-UPDATE-EXISTING-STACK";
for (var i = 0; i < changeSetChanges.Changes.length; i++) {
    var change = changeSetChanges.Changes[i];
    if (change.Type == "Resource") {
        if (change.ResourceChange.Action == "Delete") {
            return RESOURCES_BEING_DELETED_OR_REPLACED;
        }
        if (change.ResourceChange.Action == "Modify") {
            if (change.ResourceChange.Replacement == "True") {
                return RESOURCES_BEING_DELETED_OR_REPLACED;
            }
        }
    }
}
return CAN_SAFELY_UPDATE_EXISTING_STACK;

The algorithm returns different values to indicate whether the change set can be safely executed (CAN_SAFELY_UPDATE_EXISTING_STACK or RESOURCES_BEING_DELETED_OR_REPLACED). This value is used later by the state machine to decide whether to execute the change set and update the stack or interrupt the deployment.

The output of the “Inspect Change Set” stage is shown here.

{
  "environmentName": "prod",
  "stackName": "sample-lambda-app",
  "templatePath": "infra/lambda-template.yaml",
  "revisionS3Bucket": "codepipeline-us-east-1-418586629775",
  "revisionS3Key": "StepFunctionsDrivenD/CodeCommit/sjcmExZ",
  "doesStackExist": true,
  "changeSetName": "prod-sample-lambda-app-change-set-545",
  "changeSetCreationStatus": "complete",
  "changeSetAction": "CAN-SAFELY-UPDATE-EXISTING-STACK"
}

At this point, these parameters have been added to the state machine’s original input:

  • changeSetName, which is added by the “Create Change Set” state.
  • changeSetCreationStatus, which is added by the “Get Change Set Creation Status” state.
  • changeSetAction, which is added by the “Inspect Change Set Changes” state.

The “Safe to Update Infra?” step is a choice state (its JSON spec follows) that simply checks the value of the changeSetAction parameter. If the value is equal to “CAN-SAFELY-UPDATE-EXISTING-STACK“, meaning that no resources will be deleted or replaced, the step will execute the change set by proceeding to the “Execute Change Set” state. The deployment is successful (the state machine completes its execution successfully).

"Safe to Update Infra?": {
      "Type": "Choice",
      "Choices": [
        {
          "Variable": "$.taskParams.changeSetAction",
          "StringEquals": "CAN-SAFELY-UPDATE-EXISTING-STACK",
          "Next": "Execute Change Set"
        }
      ],
      "Default": "Deployment Failed"
 }

Path 3: Reject Stack Update and Fail Deployment

Reject Stack Update and Fail Deployment Execution Path

If the changeSetAction parameter is different from “CAN-SAFELY-UPDATE-EXISTING-STACK“, the state machine will interrupt the deployment by deleting the change set and proceeding to the “Deployment Fail” step, which is a built-in Fail state. (Its JSON spec follows.) This state causes the state machine to stop in a failed state and serves to indicate to the Lambda function that the pipeline deployment should be interrupted in a fail state as well.

 "Deployment Failed": {
      "Type": "Fail",
      "Cause": "Deployment Failed",
      "Error": "Deployment Failed"
    }

In all three scenarios, there’s a state machine’s visual representation available in the AWS Step Functions console that makes it very easy for developers to identify what tasks have been executed or why a deployment has failed. Developers can also inspect the inputs and outputs of each state and look at the state machine Lambda function’s logs for details. Meanwhile, the corresponding CodePipeline action remains very simple and intuitive for developers who only need to know whether the deployment was successful or failed.

The State Machine Trigger Lambda Function

The Trigger Lambda function is invoked directly by the Deploy action in CodePipeline. The CodePipeline action must pass a JSON structure to the trigger function through the UserParameters attribute, as follows:

{
  "s3Bucket": "codepipeline-StepFunctions-sample",
  "stateMachineFile": "state_machine_input.json"
}

The s3Bucket parameter specifies the S3 bucket location for the state machine input parameters file. The stateMachineFile parameter specifies the file holding the input parameters. By being able to specify different input parameters to the state machine, we make the Trigger Lambda function and the state machine reusable across environments. For example, the same state machine could be called from a test and prod pipeline action by specifying a different S3 bucket or state machine input file for each environment.

The Trigger Lambda function performs two main tasks: triggering the state machine and checking the execution state of the state machine. Its core logic is shown here:

exports.index = function (event, context, callback) {
    try {
        console.log("Event: " + JSON.stringify(event));
        console.log("Context: " + JSON.stringify(context));
        console.log("Environment Variables: " + JSON.stringify(process.env));
        if (Util.isContinuingPipelineTask(event)) {
            monitorStateMachineExecution(event, context, callback);
        }
        else {
            triggerStateMachine(event, context, callback);
        }
    }
    catch (err) {
        failure(Util.jobId(event), callback, context.invokeid, err.message);
    }
}

Util.isContinuingPipelineTask(event) is a utility function that checks if the Trigger Lambda function is being called for the first time (that is, no continuation token is passed by CodePipeline) or as a continuation of a previous call. In its first execution, the Lambda function will trigger the state machine and send a continuation token to CodePipeline that contains the state machine execution ARN. The state machine ARN is exposed to the Lambda function through a Lambda environment variable called stateMachineArn. Here is the code that triggers the state machine:

function triggerStateMachine(event, context, callback) {
    var stateMachineArn = process.env.stateMachineArn;
    var s3Bucket = Util.actionUserParameter(event, "s3Bucket");
    var stateMachineFile = Util.actionUserParameter(event, "stateMachineFile");
    getStateMachineInputData(s3Bucket, stateMachineFile)
        .then(function (data) {
            var initialParameters = data.Body.toString();
            var stateMachineInputJSON = createStateMachineInitialInput(initialParameters, event);
            console.log("State machine input JSON: " + JSON.stringify(stateMachineInputJSON));
            return stateMachineInputJSON;
        })
        .then(function (stateMachineInputJSON) {
            return triggerStateMachineExecution(stateMachineArn, stateMachineInputJSON);
        })
        .then(function (triggerStateMachineOutput) {
            var continuationToken = { "stateMachineExecutionArn": triggerStateMachineOutput.executionArn };
            var message = "State machine has been triggered: " + JSON.stringify(triggerStateMachineOutput) + ", continuationToken: " + JSON.stringify(continuationToken);
            return continueExecution(Util.jobId(event), continuationToken, callback, message);
        })
        .catch(function (err) {
            console.log("Error triggering state machine: " + stateMachineArn + ", Error: " + err.message);
            failure(Util.jobId(event), callback, context.invokeid, err.message);
        })
}

The Trigger Lambda function fetches the state machine input parameters from an S3 file, triggers the execution of the state machine using the input parameters and the stateMachineArn environment variable, and signals to CodePipeline that the execution should continue later by passing a continuation token that contains the state machine execution ARN. In case any of these operations fail and an exception is thrown, the Trigger Lambda function will fail the pipeline immediately by signaling a pipeline failure through the putJobFailureResult CodePipeline API.

If the Lambda function is continuing a previous execution, it will extract the state machine execution ARN from the continuation token and check the status of the state machine, as shown here.

function monitorStateMachineExecution(event, context, callback) {
    var stateMachineArn = process.env.stateMachineArn;
    var continuationToken = JSON.parse(Util.continuationToken(event));
    var stateMachineExecutionArn = continuationToken.stateMachineExecutionArn;
    getStateMachineExecutionStatus(stateMachineExecutionArn)
        .then(function (response) {
            if (response.status === "RUNNING") {
                var message = "Execution: " + stateMachineExecutionArn + " of state machine: " + stateMachineArn + " is still " + response.status;
                return continueExecution(Util.jobId(event), continuationToken, callback, message);
            }
            if (response.status === "SUCCEEDED") {
                var message = "Execution: " + stateMachineExecutionArn + " of state machine: " + stateMachineArn + " has: " + response.status;
                return success(Util.jobId(event), callback, message);
            }
            // FAILED, TIMED_OUT, ABORTED
            var message = "Execution: " + stateMachineExecutionArn + " of state machine: " + stateMachineArn + " has: " + response.status;
            return failure(Util.jobId(event), callback, context.invokeid, message);
        })
        .catch(function (err) {
            var message = "Error monitoring execution: " + stateMachineExecutionArn + " of state machine: " + stateMachineArn + ", Error: " + err.message;
            failure(Util.jobId(event), callback, context.invokeid, message);
        });
}

If the state machine is in the RUNNING state, the Lambda function will send the continuation token back to the CodePipeline action. This will cause CodePipeline to call the Lambda function again a few seconds later. If the state machine has SUCCEEDED, then the Lambda function will notify the CodePipeline action that the action has succeeded. In any other case (FAILURE, TIMED-OUT, or ABORT), the Lambda function will fail the pipeline action.

This behavior is especially useful for developers who are building and debugging a new state machine because a bug in the state machine can potentially leave the pipeline action hanging for long periods of time until it times out. The Trigger Lambda function prevents this.

Also, by having the Trigger Lambda function as a means to decouple the pipeline and state machine, we make the state machine more reusable. It can be triggered from anywhere, not just from a CodePipeline action.

The Pipeline in CodePipeline

Our sample pipeline contains two simple stages: the Source stage represented by a CodeCommit Git repository and the Prod stage, which contains the Deploy action that invokes the Trigger Lambda function. When the state machine decides that the change set created must be rejected (because it replaces or deletes some the existing production resources), it fails the pipeline without performing any updates to the existing infrastructure. (See the failed Deploy action in red.) Otherwise, the pipeline action succeeds, indicating that the existing provisioned infrastructure was either created (first run) or updated without impacting any resources. (See the green Deploy stage in the pipeline on the left.)

The Pipeline in CodePipeline

The JSON spec for the pipeline’s Prod stage is shown here. We use the UserParameters attribute to pass the S3 bucket and state machine input file to the Lambda function. These parameters are action-specific, which means that we can reuse the state machine in another pipeline action.

{
  "name": "Prod",
  "actions": [
      {
          "inputArtifacts": [
              {
                  "name": "CodeCommitOutput"
              }
          ],
          "name": "Deploy",
          "actionTypeId": {
              "category": "Invoke",
              "owner": "AWS",
              "version": "1",
              "provider": "Lambda"
          },
          "outputArtifacts": [],
          "configuration": {
              "FunctionName": "StateMachineTriggerLambda",
              "UserParameters": "{\"s3Bucket\": \"codepipeline-StepFunctions-sample\", \"stateMachineFile\": \"state_machine_input.json\"}"
          },
          "runOrder": 1
      }
  ]
}

Conclusion

In this blog post, we discussed how state machines in AWS Step Functions can be used to handle workflow-driven actions. We showed how a Lambda function can be used to fully decouple the pipeline and the state machine and manage their interaction. The use of a state machine greatly simplified the associated CodePipeline action, allowing us to build a much simpler and cleaner pipeline while drilling down into the state machine’s execution for troubleshooting or debugging.

Here are two exercises you can complete by using the source code.

Exercise #1: Do not fail the state machine and pipeline action after inspecting a change set that deletes or replaces resources. Instead, create a stack with a different name (think of blue/green deployments). You can do this by creating a state machine transition between the “Safe to Update Infra?” and “Create Stack” stages and passing a new stack name as input to the “Create Stack” stage.

Exercise #2: Add wait logic to the state machine to wait until the change set completes its execution before allowing the state machine to proceed to the “Deployment Succeeded” stage. Use the stack creation case as an example. You’ll have to create a Lambda function (similar to the Lambda function that checks the creation status of a stack) to get the creation status of the change set.

Have fun and share your thoughts!

About the Author

Marcilio Mendonca is a Sr. Consultant in the Canadian Professional Services Team at Amazon Web Services. He has helped AWS customers design, build, and deploy best-in-class, cloud-native AWS applications using VMs, containers, and serverless architectures. Before he joined AWS, Marcilio was a Software Development Engineer at Amazon. Marcilio also holds a Ph.D. in Computer Science. In his spare time, he enjoys playing drums, riding his motorcycle in the Toronto GTA area, and spending quality time with his family.

The Pi Hut’s 3D Xmas Tree pre-order

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/pi-hut-3d-xmas-tree/

We appreciate it’s only October, but hear us out. The Pi Hut’s 3D Xmas Tree is only available for pre-order until the 15th, and we’d hate for you to find out about it too late. So please share in a few minutes of premature Christmas cheer as we introduce you to this gorgeous kit.

The Pi Hut's 3D Xmas Tree for Raspberry Pi

Oooo…aaaaahhhh…

Super early Christmas prep

Designed by Pi Towers alumna Rachel Rayns, the 3D Xmas Tree kit is a 25-LED add-on board for the Raspberry Pi, on sale as a pre-soldered and as a ‘solder yourself’ version. You can control each LED independently via the GPIO pins, allowing you to create some wonderful, twinkly displays this coming holiday season.

The Pi Hut's 3D Xmas Tree for Raspberry Pi

The tree works with any 40-pin Raspberry Pi, including the Zero and Zero W.

You may remember the kit from last Christmas, when The Pi Hut teasingly hinted at its existence. We’ve been itching to get our hands on one for months now, and last week we finally received our own to build and play with.

3D Xmas Tree

So I took the time to record my entire build process for you…only to discover that I had managed to do most of the soldering out of frame. I blame Ben Nuttall for this, as we all rightly should, and offer instead this short GIF of me proudly showing off my finished piece.

The Pi Hut’s website has complete soldering instructions for the tree, as well as example code to get you started. Thus, even the most novice of Raspberry Pi enthusiasts and digital makers should be able to put this kit together and get it twinkling for Christmas.

If you don’t own helping hands for soldering, you’re missing out on, well, a helping hand when soldering.

If you need any help with soldering, check out our video resource. And once you’ve mastered this skill, how about upgrading your tree to twinkle in time with your favourite Christmas song? Or getting two or three, and having them flash in a beautiful synchronised multi-tree display?

Get your own 3D Xmas Tree

As mentioned above, you can pre-order the kit until Sunday 15 October. Once this deadline passes, that’s it — the boat will have sailed and you’ll be left stranded at the dock, waving goodbye to the missed opportunity.

The Pi Hut's 3D Xmas Tree for Raspberry Pi

Don’t be this kid.

With 2730 trees already ordered, you know this kit is going to be in the Christmas stocking of many a maker on 25 December.

And another thing

Shhh…while you’re there, The Pi Hut still has a few Google AIY Projects voice kits available for pre-order…but you didn’t hear that from me. Quick!

The post The Pi Hut’s 3D Xmas Tree pre-order appeared first on Raspberry Pi.

JavaScript got better while I wasn’t looking

Post Syndicated from Eevee original https://eev.ee/blog/2017/10/07/javascript-got-better-while-i-wasnt-looking/

IndustrialRobot has generously donated in order to inquire:

In the last few years there seems to have been a lot of activity with adding emojis to Unicode. Has there been an equal effort to add ‘real’ languages/glyph systems/etc?

And as always, if you don’t have anything to say on that topic, feel free to choose your own. :p

Yes.

I mean, each release of Unicode lists major new additions right at the top — Unicode 10, Unicode 9, Unicode 8, etc. They also keep fastidious notes, so you can also dig into how and why these new scripts came from, by reading e.g. the proposal for the addition of Zanabazar Square. I don’t think I have much to add here; I’m not a real linguist, I only play one on TV.

So with that out of the way, here’s something completely different!

A brief history of JavaScript

JavaScript was created in seven days, about eight thousand years ago. It was pretty rough, and it stayed rough for most of its life. But that was fine, because no one used it for anything besides having a trail of sparkles follow your mouse on their Xanga profile.

Then people discovered you could actually do a handful of useful things with JavaScript, and it saw a sharp uptick in usage. Alas, it stayed pretty rough. So we came up with polyfills and jQuerys and all kinds of miscellaneous things that tried to smooth over the rough parts, to varying degrees of success.

And… that’s it. That’s pretty much how things stayed for a while.


I have complicated feelings about JavaScript. I don’t hate it… but I certainly don’t enjoy it, either. It has some pretty neat ideas, like prototypical inheritance and “everything is a value”, but it buries them under a pile of annoying quirks and a woefully inadequate standard library. The DOM APIs don’t make things much better — they seem to be designed as though the target language were Java, rarely taking advantage of any interesting JavaScript features. And the places where the APIs overlap with the language are a hilarious mess: I have to check documentation every single time I use any API that returns a set of things, because there are at least three totally different conventions for handling that and I can’t keep them straight.

The funny thing is that I’ve been fairly happy to work with Lua, even though it shares most of the same obvious quirks as JavaScript. Both languages are weakly typed; both treat nonexistent variables and keys as simply false values, rather than errors; both have a single data structure that doubles as both a list and a map; both use 64-bit floating-point as their only numeric type (though Lua added integers very recently); both lack a standard object model; both have very tiny standard libraries. Hell, Lua doesn’t even have exceptions, not really — you have to fake them in much the same style as Perl.

And yet none of this bothers me nearly as much in Lua. The differences between the languages are very subtle, but combined they make a huge impact.

  • Lua has separate operators for addition and concatenation, so + is never ambiguous. It also has printf-style string formatting in the standard library.

  • Lua’s method calls are syntactic sugar: foo:bar() just means foo.bar(foo). Lua doesn’t even have a special this or self value; the invocant just becomes the first argument. In contrast, JavaScript invokes some hand-waved magic to set its contextual this variable, which has led to no end of confusion.

  • Lua has an iteration protocol, as well as built-in iterators for dealing with list-style or map-style data. JavaScript has a special dedicated Array type and clumsy built-in iteration syntax.

  • Lua has operator overloading and (surprisingly flexible) module importing.

  • Lua allows the keys of a map to be any value (though non-scalars are always compared by identity). JavaScript implicitly converts keys to strings — and since there’s no operator overloading, there’s no way to natively fix this.

These are fairly minor differences, in the grand scheme of language design. And almost every feature in Lua is implemented in a ridiculously simple way; in fact the entire language is described in complete detail in a single web page. So writing JavaScript is always frustrating for me: the language is so close to being much more ergonomic, and yet, it isn’t.

Or, so I thought. As it turns out, while I’ve been off doing other stuff for a few years, browser vendors have been implementing all this pie-in-the-sky stuff from “ES5” and “ES6”, whatever those are. People even upgrade their browsers now. Lo and behold, the last time I went to write JavaScript, I found out that a number of papercuts had actually been solved, and the solutions were sufficiently widely available that I could actually use them in web code.

The weird thing is that I do hear a lot about JavaScript, but the feature I’ve seen raved the most about by far is probably… built-in types for working with arrays of bytes? That’s cool and all, but not exactly the most pressing concern for me.

Anyway, if you also haven’t been keeping tabs on the world of JavaScript, here are some things we missed.

let

MDN docs — supported in Firefox 44, Chrome 41, IE 11, Safari 10

I’m pretty sure I first saw let over a decade ago. Firefox has supported it for ages, but you actually had to opt in by specifying JavaScript version 1.7. Remember JavaScript versions? You know, from back in the days when people actually suggested you write stuff like this:

1
<SCRIPT LANGUAGE="JavaScript1.2" TYPE="text/javascript">

Yikes.

Anyway, so, let declares a variable — but scoped to the immediately containing block, unlike var, which scopes to the innermost function. The trouble with var was that it was very easy to make misleading:

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3
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6
// foo exists here
while (true) {
    var foo = ...;
    ...
}
// foo exists here too

If you reused the same temporary variable name in a different block, or if you expected to be shadowing an outer foo, or if you were trying to do something with creating closures in a loop, this would cause you some trouble.

But no more, because let actually scopes the way it looks like it should, the way variable declarations do in C and friends. As an added bonus, if you refer to a variable declared with let outside of where it’s valid, you’ll get a ReferenceError instead of a silent undefined value. Hooray!

There’s one other interesting quirk to let that I can’t find explicitly documented. Consider:

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let closures = [];
for (let i = 0; i < 4; i++) {
    closures.push(function() { console.log(i); });
}
for (let j = 0; j < closures.length; j++) {
    closures[j]();
}

If this code had used var i, then it would print 4 four times, because the function-scoped var i means each closure is sharing the same i, whose final value is 4. With let, the output is 0 1 2 3, as you might expect, because each run through the loop gets its own i.

But wait, hang on.

The semantics of a C-style for are that the first expression is only evaluated once, at the very beginning. So there’s only one let i. In fact, it makes no sense for each run through the loop to have a distinct i, because the whole idea of the loop is to modify i each time with i++.

I assume this is simply a special case, since it’s what everyone expects. We expect it so much that I can’t find anyone pointing out that the usual explanation for why it works makes no sense. It has the interesting side effect that for no longer de-sugars perfectly to a while, since this will print all 4s:

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closures = [];
let i = 0;
while (i < 4) {
    closures.push(function() { console.log(i); });
    i++;
}
for (let j = 0; j < closures.length; j++) {
    closures[j]();
}

This isn’t a problem — I’m glad let works this way! — it just stands out to me as interesting. Lua doesn’t need a special case here, since it uses an iterator protocol that produces values rather than mutating a visible state variable, so there’s no problem with having the loop variable be truly distinct on each run through the loop.

Classes

MDN docs — supported in Firefox 45, Chrome 42, Safari 9, Edge 13

Prototypical inheritance is pretty cool. The way JavaScript presents it is a little bit opaque, unfortunately, which seems to confuse a lot of people. JavaScript gives you enough functionality to make it work, and even makes it sound like a first-class feature with a property outright called prototype… but to actually use it, you have to do a bunch of weird stuff that doesn’t much look like constructing an object or type.

The funny thing is, people with almost any background get along with Python just fine, and Python uses prototypical inheritance! Nobody ever seems to notice this, because Python tucks it neatly behind a class block that works enough like a Java-style class. (Python also handles inheritance without using the prototype, so it’s a little different… but I digress. Maybe in another post.)

The point is, there’s nothing fundamentally wrong with how JavaScript handles objects; the ergonomics are just terrible.

Lo! They finally added a class keyword. Or, rather, they finally made the class keyword do something; it’s been reserved this entire time.

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class Vector {
    constructor(x, y) {
        this.x = x;
        this.y = y;
    }

    get magnitude() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    }

    dot(other) {
        return this.x * other.x + this.y * other.y;
    }
}

This is all just sugar for existing features: creating a Vector function to act as the constructor, assigning a function to Vector.prototype.dot, and whatever it is you do to make a property. (Oh, there are properties. I’ll get to that in a bit.)

The class block can be used as an expression, with or without a name. It also supports prototypical inheritance with an extends clause and has a super pseudo-value for superclass calls.

It’s a little weird that the inside of the class block has its own special syntax, with function omitted and whatnot, but honestly you’d have a hard time making a class block without special syntax.

One severe omission here is that you can’t declare values inside the block, i.e. you can’t just drop a bar = 3; in there if you want all your objects to share a default attribute. The workaround is to just do this.bar = 3; inside the constructor, but I find that unsatisfying, since it defeats half the point of using prototypes.

Properties

MDN docs — supported in Firefox 4, Chrome 5, IE 9, Safari 5.1

JavaScript historically didn’t have a way to intercept attribute access, which is a travesty. And by “intercept attribute access”, I mean that you couldn’t design a value foo such that evaluating foo.bar runs some code you wrote.

Exciting news: now it does. Or, rather, you can intercept specific attributes, like in the class example above. The above magnitude definition is equivalent to:

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Object.defineProperty(Vector.prototype, 'magnitude', {
    configurable: true,
    enumerable: true,
    get: function() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    },
});

Beautiful.

And what even are these configurable and enumerable things? It seems that every single key on every single object now has its own set of three Boolean twiddles:

  • configurable means the property itself can be reconfigured with another call to Object.defineProperty.
  • enumerable means the property appears in for..in or Object.keys().
  • writable means the property value can be changed, which only applies to properties with real values rather than accessor functions.

The incredibly wild thing is that for properties defined by Object.defineProperty, configurable and enumerable default to false, meaning that by default accessor properties are immutable and invisible. Super weird.

Nice to have, though. And luckily, it turns out the same syntax as in class also works in object literals.

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Vector.prototype = {
    get magnitude() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    },
    ...
};

Alas, I’m not aware of a way to intercept arbitrary attribute access.

Another feature along the same lines is Object.seal(), which marks all of an object’s properties as non-configurable and prevents any new properties from being added to the object. The object is still mutable, but its “shape” can’t be changed. And of course you can just make the object completely immutable if you want, via setting all its properties non-writable, or just using Object.freeze().

I have mixed feelings about the ability to irrevocably change something about a dynamic runtime. It would certainly solve some gripes of former Haskell-minded colleagues, and I don’t have any compelling argument against it, but it feels like it violates some unwritten contract about dynamic languages — surely any structural change made by user code should also be able to be undone by user code?

Slurpy arguments

MDN docs — supported in Firefox 15, Chrome 47, Edge 12, Safari 10

Officially this feature is called “rest parameters”, but that’s a terrible name, no one cares about “arguments” vs “parameters”, and “slurpy” is a good word. Bless you, Perl.

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function foo(a, b, ...args) {
    // ...
}

Now you can call foo with as many arguments as you want, and every argument after the second will be collected in args as a regular array.

You can also do the reverse with the spread operator:

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let args = [];
args.push(1);
args.push(2);
args.push(3);
foo(...args);

It even works in array literals, even multiple times:

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let args2 = [...args, ...args];
console.log(args2);  // [1, 2, 3, 1, 2, 3]

Apparently there’s also a proposal for allowing the same thing with objects inside object literals.

Default arguments

MDN docs — supported in Firefox 15, Chrome 49, Edge 14, Safari 10

Yes, arguments can have defaults now. It’s more like Sass than Python — default expressions are evaluated once per call, and later default expressions can refer to earlier arguments. I don’t know how I feel about that but whatever.

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function foo(n = 1, m = n + 1, list = []) {
    ...
}

Also, unlike Python, you can have an argument with a default and follow it with an argument without a default, since the default default (!) is and always has been defined as undefined. Er, let me just write it out.

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function bar(a = 5, b) {
    ...
}

Arrow functions

MDN docs — supported in Firefox 22, Chrome 45, Edge 12, Safari 10

Perhaps the most humble improvement is the arrow function. It’s a slightly shorter way to write an anonymous function.

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(a, b, c) => { ... }
a => { ... }
() => { ... }

An arrow function does not set this or some other magical values, so you can safely use an arrow function as a quick closure inside a method without having to rebind this. Hooray!

Otherwise, arrow functions act pretty much like regular functions; you can even use all the features of regular function signatures.

Arrow functions are particularly nice in combination with all the combinator-style array functions that were added a while ago, like Array.forEach.

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[7, 8, 9].forEach(value => {
    console.log(value);
});

Symbol

MDN docs — supported in Firefox 36, Chrome 38, Edge 12, Safari 9

This isn’t quite what I’d call an exciting feature, but it’s necessary for explaining the next one. It’s actually… extremely weird.

symbol is a new kind of primitive (like number and string), not an object (like, er, Number and String). A symbol is created with Symbol('foo'). No, not new Symbol('foo'); that throws a TypeError, for, uh, some reason.

The only point of a symbol is as a unique key. You see, symbols have one very special property: they can be used as object keys, and will not be stringified. Remember, only strings can be keys in JavaScript — even the indices of an array are, semantically speaking, still strings. Symbols are a new exception to this rule.

Also, like other objects, two symbols don’t compare equal to each other: Symbol('foo') != Symbol('foo').

The result is that symbols solve one of the problems that plauges most object systems, something I’ve talked about before: interfaces. Since an interface might be implemented by any arbitrary type, and any arbitrary type might want to implement any number of arbitrary interfaces, all the method names on an interface are effectively part of a single global namespace.

I think I need to take a moment to justify that. If you have IFoo and IBar, both with a method called method, and you want to implement both on the same type… you have a problem. Because most object systems consider “interface” to mean “I have a method called method, with no way to say which interface’s method you mean. This is a hard problem to avoid, because IFoo and IBar might not even come from the same library. Occasionally languages offer a clumsy way to “rename” one method or the other, but the most common approach seems to be for interface designers to avoid names that sound “too common”. You end up with redundant mouthfuls like IFoo.foo_method.

This incredibly sucks, and the only languages I’m aware of that avoid the problem are the ML family and Rust. In Rust, you define all the methods for a particular trait (interface) in a separate block, away from the type’s “own” methods. It’s pretty slick. You can still do obj.method(), and as long as there’s only one method among all the available traits, you’ll get that one. If not, there’s syntax for explicitly saying which trait you mean, which I can’t remember because I’ve never had to use it.

Symbols are JavaScript’s answer to this problem. If you want to define some interface, you can name its methods with symbols, which are guaranteed to be unique. You just have to make sure you keep the symbol around somewhere accessible so other people can actually use it. (Or… not?)

The interesting thing is that JavaScript now has several of its own symbols built in, allowing user objects to implement features that were previously reserved for built-in types. For example, you can use the Symbol.hasInstance symbol — which is simply where the language is storing an existing symbol and is not the same as Symbol('hasInstance')! — to override instanceof:

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// oh my god don't do this though
class EvenNumber {
    static [Symbol.hasInstance](obj) {
        return obj % 2 == 0;
    }
}
console.log(2 instanceof EvenNumber);  // true
console.log(3 instanceof EvenNumber);  // false

Oh, and those brackets around Symbol.hasInstance are a sort of reverse-quoting — they indicate an expression to use where the language would normally expect a literal identifier. I think they work as object keys, too, and maybe some other places.

The equivalent in Python is to implement a method called __instancecheck__, a name which is not special in any way except that Python has reserved all method names of the form __foo__. That’s great for Python, but doesn’t really help user code. JavaScript has actually outclassed (ho ho) Python here.

Of course, obj[BobNamespace.some_method]() is not the prettiest way to call an interface method, so it’s not perfect. I imagine this would be best implemented in user code by exposing a polymorphic function, similar to how Python’s len(obj) pretty much just calls obj.__len__().

I only bring this up because it’s the plumbing behind one of the most incredible things in JavaScript that I didn’t even know about until I started writing this post. I’m so excited oh my gosh. Are you ready? It’s:

Iteration protocol

MDN docs — supported in Firefox 27, Chrome 39, Safari 10; still experimental in Edge

Yes! Amazing! JavaScript has first-class support for iteration! I can’t even believe this.

It works pretty much how you’d expect, or at least, how I’d expect. You give your object a method called Symbol.iterator, and that returns an iterator.

What’s an iterator? It’s an object with a next() method that returns the next value and whether the iterator is exhausted.

Wait, wait, wait a second. Hang on. The method is called next? Really? You didn’t go for Symbol.next? Python 2 did exactly the same thing, then realized its mistake and changed it to __next__ in Python 3. Why did you do this?

Well, anyway. My go-to test of an iterator protocol is how hard it is to write an equivalent to Python’s enumerate(), which takes a list and iterates over its values and their indices. In Python it looks like this:

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for i, value in enumerate(['one', 'two', 'three']):
    print(i, value)
# 0 one
# 1 two
# 2 three

It’s super nice to have, and I’m always amazed when languages with “strong” “support” for iteration don’t have it. Like, C# doesn’t. So if you want to iterate over a list but also need indices, you need to fall back to a C-style for loop. And if you want to iterate over a lazy or arbitrary iterable but also need indices, you need to track it yourself with a counter. Ridiculous.

Here’s my attempt at building it in JavaScript.

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function enumerate(iterable) {
    // Return a new iter*able* object with a Symbol.iterator method that
    // returns an iterator.
    return {
        [Symbol.iterator]: function() {
            let iterator = iterable[Symbol.iterator]();
            let i = 0;

            return {
                next: function() {
                    let nextval = iterator.next();
                    if (! nextval.done) {
                        nextval.value = [i, nextval.value];
                        i++;
                    }
                    return nextval;
                },
            };
        },
    };
}
for (let [i, value] of enumerate(['one', 'two', 'three'])) {
    console.log(i, value);
}
// 0 one
// 1 two
// 2 three

Incidentally, for..of (which iterates over a sequence, unlike for..in which iterates over keys — obviously) is finally supported in Edge 12. Hallelujah.

Oh, and let [i, value] is destructuring assignment, which is also a thing now and works with objects as well. You can even use the splat operator with it! Like Python! (And you can use it in function signatures! Like Python! Wait, no, Python decided that was terrible and removed it in 3…)

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let [x, y, ...others] = ['apple', 'orange', 'cherry', 'banana'];

It’s a Halloween miracle. 🎃

Generators

MDN docs — supported in Firefox 26, Chrome 39, Edge 13, Safari 10

That’s right, JavaScript has goddamn generators now. It’s basically just copying Python and adding a lot of superfluous punctuation everywhere. Not that I’m complaining.

Also, generators are themselves iterable, so I’m going to cut to the chase and rewrite my enumerate() with a generator.

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function enumerate(iterable) {
    return {
        [Symbol.iterator]: function*() {
            let i = 0;
            for (let value of iterable) {
                yield [i, value];
                i++;
            }
        },
    };
}
for (let [i, value] of enumerate(['one', 'two', 'three'])) {
    console.log(i, value);
}
// 0 one
// 1 two
// 2 three

Amazing. function* is a pretty strange choice of syntax, but whatever? I guess it also lets them make yield only act as a keyword inside a generator, for ultimate backwards compatibility.

JavaScript generators support everything Python generators do: yield* yields every item from a subsequence, like Python’s yield from; generators can return final values; you can pass values back into the generator if you iterate it by hand. No, really, I wasn’t kidding, it’s basically just copying Python. It’s great. You could now built asyncio in JavaScript!

In fact, they did that! JavaScript now has async and await. An async function returns a Promise, which is also a built-in type now. Amazing.

Sets and maps

MDN docs for MapMDN docs for Set — supported in Firefox 13, Chrome 38, IE 11, Safari 7.1

I did not save the best for last. This is much less exciting than generators. But still exciting.

The only data structure in JavaScript is the object, a map where the strings are keys. (Or now, also symbols, I guess.) That means you can’t readily use custom values as keys, nor simulate a set of arbitrary objects. And you have to worry about people mucking with Object.prototype, yikes.

But now, there’s Map and Set! Wow.

Unfortunately, because JavaScript, Map couldn’t use the indexing operators without losing the ability to have methods, so you have to use a boring old method-based API. But Map has convenient methods that plain objects don’t, like entries() to iterate over pairs of keys and values. In fact, you can use a map with for..of to get key/value pairs. So that’s nice.

Perhaps more interesting, there’s also now a WeakMap and WeakSet, where the keys are weak references. I don’t think JavaScript had any way to do weak references before this, so that’s pretty slick. There’s no obvious way to hold a weak value, but I guess you could substitute a WeakSet with only one item.

Template literals

MDN docs — supported in Firefox 34, Chrome 41, Edge 12, Safari 9

Template literals are JavaScript’s answer to string interpolation, which has historically been a huge pain in the ass because it doesn’t even have string formatting in the standard library.

They’re just strings delimited by backticks instead of quotes. They can span multiple lines and contain expressions.

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console.log(`one plus
two is ${1 + 2}`);

Someone decided it would be a good idea to allow nesting more sets of backticks inside a ${} expression, so, good luck to syntax highlighters.

However, someone also had the most incredible idea ever, which was to add syntax allowing user code to do the interpolation — so you can do custom escaping, when absolutely necessary, which is virtually never, because “escaping” means you’re building a structured format by slopping strings together willy-nilly instead of using some API that works with the structure.

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// OF COURSE, YOU SHOULDN'T BE DOING THIS ANYWAY; YOU SHOULD BUILD HTML WITH
// THE DOM API AND USE .textContent FOR LITERAL TEXT.  BUT AS AN EXAMPLE:
function html(literals, ...values) {
    let ret = [];
    literals.forEach((literal, i) => {
        if (i > 0) {
            // Is there seriously still not a built-in function for doing this?
            // Well, probably because you SHOULDN'T BE DOING IT
            ret.push(values[i - 1]
                .replace(/&/g, '&amp;')
                .replace(/</g, '&lt;')
                .replace(/>/g, '&gt;')
                .replace(/"/g, '&quot;')
                .replace(/'/g, '&apos;'));
        }
        ret.push(literal);
    });
    return ret.join('');
}
let username = 'Bob<script>';
let result = html`<b>Hello, ${username}!</b>`;
console.log(result);
// <b>Hello, Bob&lt;script&gt;!</b>

It’s a shame this feature is in JavaScript, the language where you are least likely to need it.

Trailing commas

Remember how you couldn’t do this for ages, because ass-old IE considered it a syntax error and would reject the entire script?

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{
    a: 'one',
    b: 'two',
    c: 'three',  // <- THIS GUY RIGHT HERE
}

Well now it’s part of the goddamn spec and if there’s anything in this post you can rely on, it’s this. In fact you can use AS MANY GODDAMN TRAILING COMMAS AS YOU WANT. But only in arrays.

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[1, 2, 3,,,,,,,,,,,,,,,,,,,,,,,,,]

Apparently that has the bizarre side effect of reserving extra space at the end of the array, without putting values there.

And more, probably

Like strict mode, which makes a few silent “errors” be actual errors, forces you to declare variables (no implicit globals!), and forbids the completely bozotic with block.

Or String.trim(), which trims whitespace off of strings.

Or… Math.sign()? That’s new? Seriously? Well, okay.

Or the Proxy type, which lets you customize indexing and assignment and calling. Oh. I guess that is possible, though this is a pretty weird way to do it; why not just use symbol-named methods?

You can write Unicode escapes for astral plane characters in strings (or identifiers!), as \u{XXXXXXXX}.

There’s a const now? I extremely don’t care, just name it in all caps and don’t reassign it, come on.

There’s also a mountain of other minor things, which you can peruse at your leisure via MDN or the ECMAScript compatibility tables (note the links at the top, too).

That’s all I’ve got. I still wouldn’t say I’m a big fan of JavaScript, but it’s definitely making an effort to clean up some goofy inconsistencies and solve common problems. I think I could even write some without yelling on Twitter about it now.

On the other hand, if you’re still stuck supporting IE 10 for some reason… well, er, my condolences.

Improved Testing on the AWS Lambda Console

Post Syndicated from Orr Weinstein original https://aws.amazon.com/blogs/compute/improved-testing-on-the-aws-lambda-console/

(This post has been written by Chris Tate, SDE on the Lambda Console team)

Today, AWS Lambda released three console enhancements:

  • A quicker creation flow that lets you quickly create a function with the minimum working configuration, so that you can start iterating faster.
  • A streamlined configuration page with Lambda function settings logically grouped into cards, which makes locating and making changes much easier.
  • Persisting multiple events to help test your function.

This post focuses on persisting test events, and I discuss how I’ve been using this new feature. Now when you are testing on the Lambda console, you can save up to 10 test events per function, and each event can be up to 6 megabytes in size, the maximum payload size for synchronous invocations. The events are saved for the logged-in user, so that two different users in the same account have their own set of events.

Testing Lambda functions

As a Lambda console developer, when I work on side projects at home, I sometimes use our development server. I’ve been using this new feature to test a Lambda function in one of my projects. The function is probably more complicated than it should be, because it can be triggered by an Alexa skill, Amazon CloudWatch schedule, or an Amazon API Gateway API. If you have had a similarly complicated function, you may have run into the same problem I did:  How do you test?

For quick testing, I used the console but the console used to save only one test event at a time. To work around this, my solution was a text file with three different JSON events, one for each trigger. I would copy whatever event I needed into the Lambda console, tweak it, and choose Test. This would become particularly annoying when I wanted to quickly test all three.

I also switch between my laptop and desktop depending on my mood. For that reason, I needed to make sure this text file with the events were shared in some way, as the console only locally saved one test event to the current browser. But now you don’t have to worry about any of that.

Walkthrough

In the Lambda console, go to the detail page of any function, and select Configure test events from the test events dropdown (the dropdown beside the orange test button). In the dialog box, you can manage 10 test events for your function. First, paste your Alexa trigger event in the dialog box and type an event name, such as AlexaTrigger.

Choose Create. After it saves, you see AlexaTrigger in the Test list.

When you open the dialog box again by choosing Configure test events, you are in edit mode.

To add another event, choose Create new test event. Now you can choose from a list of templates or any of your previously saved test events. This is very useful for a couple of reasons:

  • First, when you want to slightly tweak one of your existing events and still keep the earlier version intact.
  • Second, when you are not sure how to structure a particular event from an event source. You can use one of the sample event templates and tweak them to your needs. Skip it when you know what your event should be.

Paste in your CloudWatch schedule event, give it a name, and choose Create. Repeat for API Gateway.

Now that you have three events saved, you can quickly switch between them and repeatedly test. Furthermore, if you’re on your desktop but you created the test events on your laptop, there’s no problem. You can still see all your events and you can switch back and forth seamlessly between different computers.

Conclusion

This feature should allow you to more easily test your Lambda functions through the console. If you have more suggestions, add a comment to this post or submit feedback through the console. We actually read the feedback, believe it!

Backing Up WordPress

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/backing-up-wordpress/

WordPress cloud backup
WordPress logo

WordPress is the most popular CMS (Content Management System) for websites, with almost 30% of all websites in the world using WordPress. That’s a lot of sites — over 350 million!

In this post we’ll talk about the different approaches to keeping the data on your WordPress website safe.


Stop the Presses! (Or the Internet!)

As we were getting ready to publish this post, we received news from UpdraftPlus, one of the biggest WordPress plugin developers, that they are supporting Backblaze B2 as a storage solution for their backup plugin. They shipped the update (1.13.9) this week. This is great news for Backblaze customers! UpdraftPlus is also offering a 20% discount to Backblaze customers wishing to purchase or upgrade to UpdraftPlus Premium. The complete information is below.

UpdraftPlus joins backup plugin developer XCloner — Backup and Restore in supporting Backblaze B2. A third developer, BlogVault, also announced their intent to support Backblaze B2. Contact your favorite WordPress backup plugin developer and urge them to support Backblaze B2, as well.

Now, back to our post…


Your WordPress website data is on a web server that’s most likely located in a large data center. You might wonder why it is necessary to have a backup of your website if it’s in a data center. Website data can be lost in a number of ways, including mistakes by the website owner (been there), hacking, or even domain ownership dispute (I’ve seen it happen more than once). A website backup also can provide a history of changes you’ve made to the website, which can be useful. As an overall strategy, it’s best to have a backup of any data that you can’t afford to lose for personal or business reasons.

Your web hosting company might provide backup services as part of your hosting plan. If you are using their service, you should know where and how often your data is being backed up. You don’t want to find out too late that your backup plan was not adequate.

Sites on WordPress.com are automatically backed up by VaultPress (Automattic), which also is available for self-hosted WordPress installations. If you don’t want the work or decisions involved in managing the hosting for your WordPress site, WordPress.com will handle it for you. You do, however, give up some customization abilities, such as the option to add plugins of your own choice.

Very large and active websites might consider WordPress VIP by Automattic, or another premium WordPress hosting service such as Pagely.com.

This post is about backing up self-hosted WordPress sites, so we’ll focus on those options.

WordPress Backup

Backup strategies for WordPress can be divided into broad categories depending on 1) what you back up, 2) when you back up, and 3) where the data is backed up.

With server data, such as with a WordPress installation, you should plan to have three copies of the data (the 3-2-1 backup strategy). The first is the active data on the WordPress web server, the second is a backup stored on the web server or downloaded to your local computer, and the third should be in another location, such as the cloud.

We’ll talk about the different approaches to backing up WordPress, but we recommend using a WordPress plugin to handle your backups. A backup plugin can automate the task, optimize your backup storage space, and alert you of problems with your backups or WordPress itself. We’ll cover plugins in more detail, below.

What to Back Up?

The main components of your WordPress installation are:

You should decide which of these elements you wish to back up. The database is the top priority, as it contains all your website posts and pages (exclusive of media). Your current theme is important, as it likely contains customizations you’ve made. Following those in priority are any other files you’ve customized or made changes to.

You can choose to back up the WordPress core installation and plugins, if you wish, but these files can be downloaded again if necessary from the source, so you might not wish to include them. You likely have all the media files you use on your website on your local computer (which should be backed up), so it is your choice whether to back these up from the server as well.

If you wish to be able to recreate your entire website easily in case of data loss or disaster, you might choose to back up everything, though on a large website this could be a lot of data.

Generally, you should 1) prioritize any file that you’ve customized that you can’t afford to lose, and 2) decide whether you need a copy of everything in order to get your site back up quickly. These choices will determine your backup method and the amount of storage you need.

A good backup plugin for WordPress enables you to specify which files you wish to back up, and even to create separate backups and schedules for different backup contents. That’s another good reason to use a plugin for backing up WordPress.

When to Back Up?

You can back up manually at any time by using the Export tool in WordPress. This is handy if you wish to do a quick backup of your site or parts of it. Since it is manual, however, it is not a part of a dependable backup plan that should be done regularly. If you wish to use this tool, go to Tools, Export, and select what you wish to back up. The output will be an XML file that uses the WordPress Extended RSS format, also known as WXR. You can create a WXR file that contains all of the information on your site or just portions of the site, such as posts or pages by selecting: All content, Posts, Pages, or Media.
Note: You can use WordPress’s Export tool for sites hosted on WordPress.com, as well.

Export instruction for WordPress

Many of the backup plugins we’ll be discussing later also let you do a manual backup on demand in addition to regularly scheduled or continuous backups.

Note:  Another use of the WordPress Export tool and the WXR file is to transfer or clone your website to another server. Once you have exported the WXR file from the website you wish to transfer from, you can import the WXR file from the Tools, Import menu on the new WordPress destination site. Be aware that there are file size limits depending on the settings on your web server. See the WordPress Codex entry for more information. To make this job easier, you may wish to use one of a number of WordPress plugins designed specifically for this task.

You also can manually back up the WordPress MySQL database using a number of tools or a plugin. The WordPress Codex has good information on this. All WordPress plugins will handle this for you and do it automatically. They also typically include tools for optimizing the database tables, which is just good housekeeping.

A dependable backup strategy doesn’t rely on manual backups, which means you should consider using one of the many backup plugins available either free or for purchase. We’ll talk more about them below.

Which Format To Back Up In?

In addition to the WordPress WXR format, plugins and server tools will use various file formats and compression algorithms to store and compress your backup. You may get to choose between zip, tar, tar.gz, tar.gz2, and others. See The Most Common Archive File Formats for more information on these formats.

Select a format that you know you can access and unarchive should you need access to your backup. All of these formats are standard and supported across operating systems, though you might need to download a utility to access the file.

Where To Back Up?

Once you have your data in a suitable format for backup, where do you back it up to?

We want to have multiple copies of our active website data, so we’ll choose more than one destination for our backup data. The backup plugins we’ll discuss below enable you to specify one or more possible destinations for your backup. The possible destinations for your backup include:

A backup folder on your web server
A backup folder on your web server is an OK solution if you also have a copy elsewhere. Depending on your hosting plan, the size of your site, and what you include in the backup, you may or may not have sufficient disk space on the web server. Some backup plugins allow you to configure the plugin to keep only a certain number of recent backups and delete older ones, saving you disk space on the server.
Email to you
Because email servers have size limitations, the email option is not the best one to use unless you use it to specifically back up just the database or your main theme files.
FTP, SFTP, SCP, WebDAV
FTP, SFTP, SCP, and WebDAV are all widely-supported protocols for transferring files over the internet and can be used if you have access credentials to another server or supported storage device that is suitable for storing a backup.
Sync service (Dropbox, SugarSync, Google Drive, OneDrive)
A sync service is another possible server storage location though it can be a pricier choice depending on the plan you have and how much you wish to store.
Cloud storage (Backblaze B2, Amazon S3, Google Cloud, Microsoft Azure, Rackspace)
A cloud storage service can be an inexpensive and flexible option with pay-as-you go pricing for storing backups and other data.

A good website backup strategy would be to have multiple backups of your website data: one in a backup folder on your web hosting server, one downloaded to your local computer, and one in the cloud, such as with Backblaze B2.

If I had to choose just one of these, I would choose backing up to the cloud because it is geographically separated from both your local computer and your web host, it uses fault-tolerant and redundant data storage technologies to protect your data, and it is available from anywhere if you need to restore your site.

Backup Plugins for WordPress

Probably the easiest and most common way to implement a solid backup strategy for WordPress is to use one of the many backup plugins available for WordPress. Fortunately, there are a number of good ones and are available free or in “freemium” plans in which you can use the free version and pay for more features and capabilities only if you need them. The premium options can give you more flexibility in configuring backups or have additional options for where you can store the backups.

How to Choose a WordPress Backup Plugin

screenshot of WordPress plugins search

When considering which plugin to use, you should take into account a number of factors in making your choice.

Is the plugin actively maintained and up-to-date? You can determine this from the listing in the WordPress Plugin Repository. You also can look at reviews and support comments to get an idea of user satisfaction and how well issues are resolved.

Does the plugin work with your web hosting provider? Generally, well-supported plugins do, but you might want to check to make sure there are no issues with your hosting provider.

Does it support the cloud service or protocol you wish to use? This can be determined from looking at the listing in the WordPress Plugin Repository or on the developer’s website. Developers often will add support for cloud services or other backup destinations based on user demand, so let the developer know if there is a feature or backup destination you’d like them to add to their plugin.

Other features and options to consider in choosing a backup plugin are:

  • Whether encryption of your backup data is available
  • What are the options for automatically deleting backups from the storage destination?
  • Can you globally exclude files, folders, and specific types of files from the backup?
  • Do the options for scheduling automatic backups meet your needs for frequency?
  • Can you exclude/include specific database tables (a good way to save space in your backup)?

WordPress Backup Plugins Review

Let’s review a few of the top choices for WordPress backup plugins.

UpdraftPlus

UpdraftPlus is one of the most popular backup plugins for WordPress with over one million active installations. It is available in both free and Premium versions.

UpdraftPlus just released support for Backblaze B2 Cloud Storage in their 1.13.9 update on September 25. According to the developer, support for Backblaze B2 was the most frequent request for a new storage option for their plugin. B2 support is available in their Premium plugin and as a stand-alone update to their standard product.

Note: The developers of UpdraftPlus are offering a special 20% discount to Backblaze customers on the purchase of UpdraftPlus Premium by using the coupon code backblaze20. The discount is valid until the end of Friday, October 6th, 2017.

screenshot of Backblaze B2 cloud backup for WordPress in UpdraftPlus

XCloner — Backup and Restore

XCloner — Backup and Restore is a useful open-source plugin with many options for backing up WordPress.

XCloner supports B2 Cloud Storage in their free plugin.

screenshot of XCloner WordPress Backblaze B2 backup settings

BlogVault

BlogVault describes themselves as a “complete WordPress backup solution.” They offer a free trial of their paid WordPress backup subscription service that features real-time backups of changes to your WordPress site, as well as many other features.

BlogVault has announced their intent to support Backblaze B2 Cloud Storage in a future update.

screenshot of BlogValut WordPress Backup settings

BackWPup

BackWPup is a popular and free option for backing up WordPress. It supports a number of options for storing your backup, including the cloud, FTP, email, or on your local computer.

screenshot of BackWPup WordPress backup settings

WPBackItUp

WPBackItUp has been around since 2012 and is highly rated. It has both free and paid versions.

screenshot of WPBackItUp WordPress backup settings

VaultPress

VaultPress is part of Automattic’s well-known WordPress product, JetPack. You will need a JetPack subscription plan to use VaultPress. There are different pricing plans with different sets of features.

screenshot of VaultPress backup settings

Backup by Supsystic

Backup by Supsystic supports a number of options for backup destinations, encryption, and scheduling.

screenshot of Backup by Supsystic backup settings

BackupWordPress

BackUpWordPress is an open-source project on Github that has a popular and active following and many positive reviews.

screenshot of BackupWordPress WordPress backup settings

BackupBuddy

BackupBuddy, from iThemes, is the old-timer of backup plugins, having been around since 2010. iThemes knows a lot about WordPress, as they develop plugins, themes, utilities, and provide training in WordPress.

BackupBuddy’s backup includes all WordPress files, all files in the WordPress Media library, WordPress themes, and plugins. BackupBuddy generates a downloadable zip file of the entire WordPress website. Remote storage destinations also are supported.

screenshot of BackupBuddy settings

WordPress and the Cloud

Do you use WordPress and back up to the cloud? We’d like to hear about it. We’d also like to hear whether you are interested in using B2 Cloud Storage for storing media files served by WordPress. If you are, we’ll write about it in a future post.

In the meantime, keep your eye out for new plugins supporting Backblaze B2, or better yet, urge them to support B2 if they’re not already.

The Best Backup Strategy is the One You Use

There are other approaches and tools for backing up WordPress that you might use. If you have an approach that works for you, we’d love to hear about it in the comments.

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